Free Online Calculators
For Everyone
Accurate, accessible, and completely free. Every calculator is personally verified against official standards — no ads to click through, no signup required.
Browse Calculatorscraft Calculators
View all →Aspect Ratio Calculator — Find, Convert & Resize
Find the simplified aspect ratio from width and height, solve for a missing dimension from a target ratio, or resize proportionally without distortion.
Quilt Fabric Calculator: Yardage for Top, Backing & Binding
Calculate quilt fabric yardage for top, backing, and binding. Choose quilt size and number of fabrics — get yards per color, backing panels, and binding.
Cross Stitch Calculator: Fabric Size, Stitch Count & Floss
Cross stitch calculator: enter stitch count and fabric type, get finished size, buy size, hoop recommendation, floss skeins, and time estimate. Inches and cm.
education Calculators
View all →GRE & GMAT Score Calculator — Percentile & Total Score
Convert GRE Verbal and Quant scores into percentiles, or record your GMAT Focus Edition Total Score against the current mean. Official ETS/GMAC data.
JLPT Calculator — Pass Mark & Sectional Minimum Checker
Check whether your JLPT N1-N5 scores pass. Enter section scores to see your total and whether you cleared every sectional minimum.
SHSAT Score Calculator — Composite Score Recorder
Add your SHSAT ELA and Math scaled scores into a composite. Explains why there's no raw-to-scale table and why admission cutoffs aren't fixed.
MCAT Score Calculator — Total Score & Percentile Estimate
Add up your four MCAT section scores into a Total Score (472-528) and estimate your percentile rank using AAMC's current-cycle mean and standard deviation.
ACT Score Calculator — Composite Score & SAT Concordance
Calculate your ACT Composite score (Enhanced or Legacy) and convert it to an equivalent SAT score using the official 2018 ACT/SAT concordance tables.
GPA Calculator — Weighted & Cumulative GPA
Calculate weighted or unweighted GPA by course, or combine a prior GPA with a new semester. 4.0-scale grade points with Honors/AP bonuses.
AP Score Calculator — Estimate Your 1-5 AP Exam Score
Estimate your AP exam score (1-5) from composite points earned, with subject-specific historical curve thresholds for 10 major AP exams.
Scientific Notation Calculator — Convert & Calculate
Convert numbers to scientific, E, and engineering notation, or perform add/subtract/multiply/divide arithmetic directly in scientific notation.
Weighted Grade Calculator — Category Weights & Grade Needed
Calculate your weighted course grade from category weights and scores, plus the exact score needed on a remaining exam to hit your target grade.
engineering Calculators
View all →Towing Capacity Calculator — Max Trailer Weight & Payload
Calculate your max trailer weight, payload capacity, and recommended tongue weight from your vehicle's GCWR, GVWR, and curb weight.
Voltage Drop Calculator — NEC Formula, Single & 3-Phase
Calculate voltage drop and percentage for any wire run using the NEC formula. Single-phase and three-phase, copper or aluminum, full AWG table.
Acreage Calculator — Land Area Converter & Parcel Size
Convert acres, square feet, hectares, and square yards, or calculate acreage from a rectangular parcel's length and width — plus a football-field comparison.
Power-to-Weight Ratio Calculator: hp/ton & W/kg
Calculate power-to-weight ratio for cars (hp/ton), cycling (W/kg with pro benchmark tiers), or general machinery (kW/kg). Instant results.
Chain Rule Calculator — Step-by-Step Derivatives
Calculate derivatives of composite functions using the chain rule. Picks outer and inner function, shows u-substitution steps, dy/du, du/dx, and final answer.
Density Altitude Calculator for Pilots
Calculate density altitude from elevation, altimeter setting, and OAT. Shows pressure altitude, ISA deviation, performance level, and humidity note.
Crosswind Component Calculator for Pilots
Calculate crosswind and headwind from wind direction, speed, and runway. Includes gust components, opposite runway, aircraft limit check, and clock method tip.
Pulley RPM Calculator: Speed Ratio, Belt Length & Torque
Calculate driven pulley RPM, belt length, speed ratio, and torque for any belt drive. Imperial and metric. Supports V-belt, flat belt, and timing belt drives.
fashion Calculators
View all →finance Calculators
View all →529 College Savings Calculator — Growth & Superfunding
Project 529 plan growth from monthly contributions, plus a gift-tax exclusion and 5-year superfunding calculator for 2026 limits.
Home Appreciation Calculator — Historical CAGR & Forward Projection
Calculate your home's actual historical appreciation rate (CAGR) or project a future value using an adjustable annual rate, based on FHFA HPI data.
Cash Back Calculator — Flat-Rate vs Rotating Category
Calculate flat-rate or rotating-category cash back, including quarterly caps, then compare which card type earns more for your spend.
Niche Loan Calculator — Bridge Loan & Hard Money Loan
Calculate interest-only payments, points cost, and total cost for bridge loans and hard money loans — short-term, asset-based real estate financing.
Retirement Withdrawal Calculator — 401(k), Match & IRA RMD
Estimate 401(k) early withdrawal penalties, employer match dollars, and IRA required minimum distributions in one free calculator.
Reverse Mortgage Calculator — HECM Proceeds Estimate
Estimate HECM reverse mortgage principal limit and net proceeds using the 2026 $1,249,125 claim cap. Illustrative estimate, not the official HUD PLF.
Alimony Calculator — CA, NY & TX Spousal Support
Estimate spousal support with California's temporary guideline, New York's statutory formula, or Texas's cap — most states use judicial discretion instead.
Credit Card Minimum Payment Calculator — Payoff Trap
Calculate your credit card's minimum payment using two common issuer formulas, then see how many years paying only the minimum actually takes.
Import Duty Calculator — US Customs Duty & Fee Estimator
Estimate US import duty, MPF, and HMF using your own HTS duty rate. Covers the de minimis suspension, Section 122/232/301 surcharges, and FOB vs CIF value.
Real Estate Commission Calculator — Listing & Buyer Agent Split
Calculate real estate agent commission with independently adjustable listing and buyer-agent rates, reflecting the 2024 NAR settlement changes.
Unit Price Calculator — Compare Cost Per Oz, Liter & More
Compare 2-4 products of different sizes to find the true cost per ounce, pound, gram, liter, gallon, or item — and see which one is the best value.
Divorce Buyout Calculator — House Equity Buyout Estimate
Calculate the home equity buyout amount owed to a spouse in a divorce, with an optional notional selling-cost adjustment and refinance note.
Medical RVU Calculator — Payment, Global Period, 8-Min Rule
Calculate Medicare RVU payment with the 2026 conversion factor, check global surgical period billing rules, and convert therapy minutes to units.
Balance Transfer Calculator — 0% APR Payoff Savings
See if a balance transfer actually saves money after the fee. Compares total interest paid vs your current card, with a deferred-interest payoff warning.
Severance Pay Calculator — Estimate + WARN Act Check
Estimate severance pay from weekly pay or salary, years of service, and a weeks-per-year rate. Includes a WARN Act notice check.
Mobile Home Loan Calculator — Chattel Loan Payments
Calculate manufactured home chattel loan payments and total interest, plus FHA Title I loan limits — built for mobile home financing, not a standard mortgage.
Money Market Account Calculator — Tiered APY & Growth
Calculate money market account growth with tiered APY rates and monthly contributions. See exactly how balance tiers blend into your effective rate.
PTO Calculator — Accrual Rate & Balance Projector
Calculate PTO accrual per pay period or project your future vacation balance with rollover caps and use-it-or-lose-it rules by state.
Stock Profit Calculator — Return %, Fees & Break-Even
Calculate stock trading profit or loss, return percentage, and break-even price after fees. Includes dividends and short vs long-term capital gains context.
1099 Tax Calculator — Self-Employment Tax & Quarterly Payments
Estimate self-employment tax, federal income tax, and quarterly payments on 1099 income for 2026 — includes the SS wage base cap and Additional Medicare Tax.
USCIS Fee Calculator: Immigration Filing Costs 2026
Calculate USCIS filing fees for N-400, I-485, I-765, I-130, I-129 H-1B and more. Combine forms for a total cost, plus 2025 HR-1 asylum-related fees.
CD Calculator — Certificate of Deposit Interest
Calculate your Certificate of Deposit's value at maturity from principal, APY, and term. Includes an early withdrawal penalty estimate.
FERS & TSP Calculator — Federal Pension + Thrift Savings Plan
Estimate your FERS annual pension and project your TSP balance growth with agency matching. For federal employees planning retirement.
Mortgage Recast Calculator — Lower Your Payment Without Refinancing
See how much a lump-sum principal payment lowers your monthly mortgage payment via recasting — same rate, same payoff date, no refinance.
CPM Calculator — Cost Per Mille & Ad Cost Solver
Solve for CPM, total ad cost, or impressions from any two known values. Includes bonus CPC and CTR calculation and platform CPM benchmarks.
High-Yield Savings Calculator — HYSA Growth & Comparison
Calculate HYSA growth with monthly contributions and see exactly how much more interest you'd earn vs a traditional bank's average 0.38% APY.
No-Vig Calculator — Fair Odds & Devig Sports Betting
Remove the sportsbook vig from American odds to find true implied probability and fair odds for both sides of a two-way market.
NPS Calculator — Net Promoter Score
Calculate your Net Promoter Score from response counts or raw 0-10 ratings, with Promoter/Passive/Detractor breakdown and industry benchmark tiers.
Pay Raise Calculator — Salary Increase & Real Raise
Solve for new salary, raise percentage, or dollar increase. See the per-paycheck impact and your real raise after inflation.
Paycheck Calculator — Take-Home Pay by State (2026)
Calculate net take-home pay for any US state with 2026 federal brackets, FICA, and detailed state tax. Covers all 9 no-tax and 14 flat-tax states plus CA/NY.
Scrap Gold Calculator — Melt Value by Karat & Weight
Calculate scrap gold melt value from karat, weight, and spot price. Supports grams, pennyweight, troy oz, and estimated dealer payout percentage.
Scrap Silver Calculator — Melt Value by Purity & Weight
Calculate scrap silver melt value from purity (sterling, coin, fine), weight, and spot price. Includes estimated dealer payout percentage.
Share Incentive Plan (SIP) Calculator — UK Employee Shares
Calculate UK SIP shares from partnership, matching, and free shares, plus tax saved and tax owed by holding period under 2025/26 HMRC rules.
403(b) Calculator — Project Your Retirement Savings
Calculate 403(b) retirement savings with employer match, catch-up contributions, fee drag, and Traditional vs Roth after-tax comparison.
Indiana Child Support Calculator (2024 Guidelines)
Estimate Indiana child support using the 2024 Income Shares guidelines — BSO lookup, NCP share, parenting time credit, childcare, and insurance add-ons.
Law School Admissions Calculator — LSAT & GPA Chances
Estimate law school admission chances by LSAT, GPA, URM status, and work experience. Covers T14 through T50 schools with reach/target/safety.
Reverse Tax Calculator — Find Pre-Tax Price from Total
Work backwards from total price to find pre-tax amount and tax paid. US state rates, VAT, GST, HST presets included. Supports multiple items.
SCHD Dividend Calculator — Income & DRIP Projections
Calculate SCHD dividend income, DRIP growth, and shares needed for target income. Year-by-year projections with quarterly payment schedule.
Copart Fee Calculator: Buyer Fees & Total Cost 2026
Calculate Copart buyer fees, virtual bid fees, gate fees, and total cost. Full 2026 fee schedule for secured and unsecured payments included.
Grailed Fee Calculator: Seller Fees & Net Payout 2026
Calculate Grailed seller fees, net payout, and profit. Full 2026 fee schedule — 9% commission on sale + shipping, all payment scenarios, reverse pricing mode.
GM Income Calculator: Monthly Income for GM Financial
Convert hourly, salary, bi-weekly, semi-monthly, or YTD pay to monthly gross income — the exact figure GM Financial uses to evaluate your auto loan.
fitness Calculators
View all →Navy Body Fat Calculator — Circumference Method
Estimate body fat using the US Navy circumference method (neck, waist, height, plus hip for women). Instant %BF with fitness category.
Weight Loss Percentage Calculator — % Lost & Goal Tracker
Find your weight loss percentage, track progress toward a goal weight, and see pounds remaining, plus a healthy pace check using the 0.5-1%/week guideline.
Batting Average Calculator — AVG, OBP, SLG & OPS
Calculate batting average from at-bats and hits, plus OBP, slugging percentage, and OPS from a full stat line. Correct no-leading-zero display.
Activity Calorie Calculator — Walking, Running, Cycling
Estimate calories burned walking, running, cycling, or on the treadmill using MET values from the Compendium of Physical Activities. Enter weight and duration.
Army Body Fat Calculator — 2024 One-Site Tape Test
Estimate Army body fat using the official 2024 one-site tape method or the legacy 3-site formula. Checks against age-based standards.
ERA Calculator — Earned Run Average & WHIP
Calculate ERA from innings pitched and earned runs, with correct baseball innings notation (outs, not decimals). Includes bonus WHIP calculation.
FFMI Calculator — Fat-Free Mass Index & Natural Limit
Calculate FFMI and normalized FFMI from weight, height, and body fat %. See where you fall vs the ~25 natural genetic limit from the Kouri et al. study.
DOTS Powerlifting Calculator: Score Your Squat, Bench & Deadlift
Calculate DOTS and Wilks scores from your powerlifting total. Bodyweight-adjusted for fair comparison across all weight classes and sexes.
RPE Calculator — Estimate 1RM & Find Training Weights
Calculate estimated 1RM from RPE, find target weights for any rep/RPE combo, and plan backoff sets using the Tuchscherer RTS chart.
Rucking Calorie Calculator: Calories Burned by Weight & Pace
Calculate rucking calories burned using the Pandolf equation. Enter body weight, pack weight, speed, grade, and terrain for precise results.
Warmup Sets Calculator: Barbell Warmup & Plate Loading Guide
Calculate barbell warmup sets by percentage for any working weight. Three protocols: Standard, Starting Strength, and Competition. Plate loading included.
gaming Calculators
View all →Balatro Calculator — Chips × Mult Score Breakdown
Calculate your Balatro poker hand score step by step: base Chips × Mult, card chip values, and flat vs. multiplicative joker bonuses.
Robux Tax Calculator — Marketplace Fee & DevEx Cash-Out
Calculate the 30% Roblox marketplace fee on item sales and convert Earned Robux to USD at the current DevEx cash-out rate.
Uma Musume Affinity Calculator — Bond Level Planner
Find how much bond a support card needs to hit the 40/60/80/100 friendship thresholds and roughly how many training sessions that takes.
D&D Calculator — Point Buy, Dice, Encounter & HP
D&D 5e (2014) point buy, dice average, encounter difficulty, and hit points calculators in one tool for tabletop players and DMs.
Minecraft Nether Portal Calculator — Coordinates & Frame Size
Convert Overworld and Nether coordinates with the 1:8 ratio, and check portal frame size and link search radius in Minecraft Java and Bedrock.
OSRS Combat Calculator — Combat Level, DPS & Prayer Drain
Calculate your Old School RuneScape combat level, weapon DPS, and prayer point drain time — three combat tools in one calculator.
Fantasy Football Points Calculator — Standard, Half & Full PPR
Calculate fantasy football points from a full stat line in Standard, Half-PPR, Full PPR, or custom scoring, with a passing/rushing/receiving breakdown.
OSRS Dry Calculator — Drop Rate & Streak Probability
Calculate your true drop chance in Old School RuneScape from drop rate and kill count, plus kills needed for 50/90/99% confidence. Includes item presets.
The Forge Calculator — Roblox Ore Multiplier & Trait Odds
Calculate combined forge multiplier and trait composition percentage for Roblox's The Forge, using your own ore multiplier values so it never goes out of date.
Uma Musume Stamina Calculator — Race Distance Requirements
Check if your Uma Musume's stamina stat meets the recommended minimum for Sprint, Mile, Medium, or Long races, adjusted for running style and recovery skills.
Vorici Calculator — Path of Exile Chromatic Orbs
Calculate expected chromatic orbs for PoE socket colors. Compare random rolling vs Vorici bench with mean, 90th, and 99th percentile costs.
Total Battle Calculator: Troop Stacking & Army Power
Total Battle troop stacking calculator. Enter leadership cap and primary troop tier to get optimal stack composition, shield counts, and effective army power.
health Calculators
View all →Caffeine Calculator — Content Tracker & Half-Life
Log drinks to track daily caffeine intake vs the FDA's 400 mg benchmark, or find how much caffeine remains in your system via the half-life formula.
Gestational Age Calculator — Due Date, Conception & Implantation
Calculate due date, conception date, and implantation window from your LMP using Naegele's Rule. See your current gestational age in weeks and days.
Water Fasting Calculator — Stage & Safety Guide
Find which physiological stage your planned water fast falls in, plus a prominent safety checklist and physician-supervision guidance for extended fasts.
AST/ALT Ratio Calculator — De Ritis Ratio
Calculate the AST/ALT ratio (De Ritis ratio) from your liver panel and see what the pattern typically suggests, alongside individual normal-range checks.
CHA2DS2-VASc Score Calculator — AFib Stroke Risk
Calculate CHA2DS2-VASc score for atrial fibrillation stroke risk. Checkbox-based scoring with annual stroke risk % and anticoagulation context.
Cholesterol Ratio Calculator (TC/HDL + LDL)
Calculate your total cholesterol/HDL ratio and estimate LDL with the Friedewald equation. See risk categories against AHA and CDC reference ranges.
Kidney Function Calculator — BUN/Cr, FENa, Osmolality
Calculate BUN/creatinine ratio, FENa (fractional excretion of sodium), and calculated serum osmolality with osmolar gap — clinical AKI interpretation aids.
Vertex Distance Calculator — Glasses to Contact Lens Power
Convert glasses power to contact lens power (or back) using the vertex distance formula, plus the ±4.00 D clinical significance threshold.
PT Assessment Calculator — Balance, Mobility & ARDS Tools
Berg Balance Scale, Elderly Mobility Scale, tidal volume (Devine/ARDSNet), and PF ratio (Berlin ARDS) calculators for PT and allied health assessment scoring.
Free Water Deficit Calculator — Hypernatremia Correction
Calculate free water deficit for hypernatremia from body weight, age/sex TBW fraction, and serum sodium. Includes the 0.5 mEq/L/hour safe correction limit.
Prostate Volume Calculator — Ellipsoid Method & PSA Density
Calculate prostate volume from length, width, and height using the ellipsoid formula, plus PSA density (PSAD) with the 0.15 and 0.20 thresholds.
Baby Percentile Calculator — Weight & Height for Age
Find your child's WHO/CDC growth percentile for weight-for-age or height/length-for-age using the official LMS method. Boys and girls, 0-20 years.
Blood Alcohol Level Calculator (BAC Estimator)
Estimate blood alcohol content from drinks, weight, and time using the Widmark equation. Educational only — never use to decide if it's safe to drive.
Keto Calculator — Macros, Calories & Net Carbs
Calculate your daily keto macros — fat, protein, and carb grams — from your BMR, TDEE, and goal, plus a net carbs helper for reading food labels.
A1C Calculator — A1C to Average Glucose (eAG) Converter
Convert A1C to estimated average glucose (eAG) in mg/dL or mmol/L, or IFCC mmol/mol. Bidirectional conversion with ADA normal/prediabetes/diabetes ranges.
BSA Calculator — Body Surface Area (Mosteller, DuBois, Haycock)
Calculate body surface area using Mosteller, DuBois, and Haycock formulas side by side. Includes an optional mg/m² dosing reference field.
Chronological Age Calculator for Testing & Assessments
Calculate exact chronological age in years, months, and days for WISC-V, WAIS-IV, and KTEA testing. Includes Pearson rounding and corrected age for preemies.
Corrected Calcium Calculator (Payne Formula)
Calculate albumin-corrected serum calcium using the Payne formula. mg/dL and mmol/L supported, with hypocalcemia/hypercalcemia severity tiers.
Fasting Calculator — Fasting Window & Stage Tracker
Calculate your intermittent fasting window for 16:8, 18:6, 20:4, OMAD, or custom protocols, with a live stage tracker showing ketosis and autophagy timing.
Fib-4 Calculator — Liver Fibrosis Risk Score
Calculate the FIB-4 index from age, AST, ALT, and platelet count. Includes the age-adjusted low-risk cutoff for patients 65 and older.
Half Birthday Calculator — Find Your 1/2 Birthday
Find your half birthday using the calendar (+6 months) or day-count (+182/183 days) method, with the exact date and countdown to the next one.
HOMA-IR Calculator — Insulin Resistance Score
Calculate HOMA-IR from fasting glucose and fasting insulin, in mg/dL or mmol/L. See where your score falls vs optimal, normal, and insulin-resistant ranges.
Invisalign Cost Calculator: 2026 Prices by Complexity & Insurance
Estimate Invisalign treatment cost by complexity, insurance, location, and provider type. Shows after-insurance cost and monthly payment breakdown.
NASCET Calculator: Carotid Artery Stenosis Percentage
NASCET carotid stenosis calculator. Enter stenosis and distal ICA diameters to get NASCET %, severity category, ECST equivalent, and CEA treatment thresholds.
Prescription Refill Date Calculator: When Can I Refill My Medication?
Calculate when you can refill a prescription based on fill date, days supply, and insurance policy. Track multiple medications with status alerts.
home Calculators
View all →Fence Post Depth Calculator — Hole Depth & Diameter
Find the right fence post hole depth using the 1/3-length rule, your frost line, and the 12 in IBC minimum — plus hole diameter and concrete volume.
Concrete Bag Calculator — How Many Bags Do I Need?
Calculate how many 40, 60, or 80 lb bags of concrete you need for a slab, footing, or post — plus total weight and cost estimate.
Electricity Cost Calculator — What Does It Cost to Run?
Calculate the daily, monthly, and annual cost to run any appliance from its wattage, hours used, and electricity rate. Add devices for a household total.
Flooring Installation Cost Calculator — Laminate, Carpet, Rug Pad
Estimate laminate, carpet, and rug pad installation costs by room size and material tier, including the sq ft to sq yd carpet conversion.
Insulation Calculator — Attic R-Value & Blown-In Cost
Find your recommended attic R-value by climate zone, then calculate blown-in insulation depth and installed cost for fiberglass or cellulose.
Window Replacement Cost Calculator — By Material
Estimate window replacement cost by material (vinyl, wood, fiberglass) and insert vs. full-frame installation, with a low-high price range for your project.
Asphalt Driveway Cost Calculator — Install & Resurface
Estimate asphalt driveway cost by size, project type, and thickness. Compare new installation vs resurface/overlay pricing with a low-high range.
Furnace Size Calculator — BTU & AC Tonnage Estimator
Estimate furnace BTU/hr and AC tonnage from square footage, climate zone, and insulation quality — a rough pre-Manual J sizing check, not a replacement for one.
Tree Removal Cost Calculator: 2026 Price Estimate
Estimate tree removal cost by height, plus stump removal, difficult-access, and emergency premiums. 2026 US pricing ranges for budgeting.
Board and Batten Calculator — Spacing & Materials
Calculate how many battens you need, exact spacing, and total linear feet of material for a board and batten wall — plus a paint estimate.
Plywood Calculator — Sheets Needed & Cost
Calculate how many plywood sheets you need by area, sheet size, and waste factor — plus cost estimate and a simple layout suggestion.
Tire Pressure Calculator — Temperature Adjuster & Guide
Adjust tire PSI for temperature swings and get vehicle-specific guidance on finding your correct cold tire pressure spec.
Landscaping Gravel Calculator — Tons & Cost
Calculate how many tons of gravel you need for a driveway, walkway, or garden bed by area, depth, and material — plus cost estimate.
Pool Volume Calculator — Gallons for Any Shape
Calculate your swimming pool's volume in gallons and liters for rectangular, round, or oval pools, including sloped-bottom depth averaging.
Cinder Block Calculator
Calculate how many cinder blocks you need for a wall. Cinder blocks are the same as concrete masonry units (CMU) — this calculator covers all standard sizes.
Concrete Block Calculator (CMU & Cinder Block)
Calculate blocks needed for any wall — includes mortar bags, courses, door/window openings, waste factor, and cost. Works for CMU and cinder blocks.
House Repiping Cost Calculator: PEX vs Copper vs CPVC 2026
Estimate house repiping cost by square footage, pipe material, and bathroom count. Compare PEX vs copper vs CPVC with 2026 labor and material rates.
Drapery Yardage Calculator: Pinch Pleat, Ripplefold & Stack Back
Calculate drapery yardage for pinch pleat, ripplefold, French pleat, wave, and flat styles. Includes stack back calculation. Works in yards and metres.
Roman Blind Calculator: Fabric, Folds & Rods
Calculate fabric, fold count, and rods for flat and cascade roman blinds. Covers inside and outside mount, lining, and works in cm and inches.
Curtain Fabric Calculator: Yardage for Every Heading Style
Calculate curtain fabric yardage for eyelet, pencil pleat, pinch pleat, and wave curtains. Enter window width, drop, and lining type for exact fabric needed.
Cushion Fabric Calculator: Box, Knife-Edge & Round Cushions
Calculate fabric for box, knife-edge, and round cushions. Covers sofa, chair, bench, and outdoor pads with seam allowances, piping, and multiple quantities.
lifestyle Calculators
View all →Days Until Calculator — Countdown to Any Date
Find out exactly how many days until any date, with weeks and months breakdown, day of the week, and support for multiple saved countdowns.
Speaking Pace & Reading Time Calculator
Estimate speech or presentation time from word count and pace, or find reading time for silent reading and reading aloud using research-based speeds.
Words Per Minute Calculator — Gross & Net WPM
Calculate your typing speed in words per minute from characters typed or word count, plus accuracy-adjusted Net WPM and a speed benchmark tier.
outdoor Calculators
View all →Arrow FOC Calculator — Front of Center for Archery
Calculate arrow Front of Center (FOC%) from length and balance point, or from individual components. Ratings for target, hunting, and extreme FOC applications.
Tarp Size Calculator: What Size Tarp Do I Need?
Calculate what size tarp you need for hay bales, flatbed trucks, pools, and ground cover. Recommends the nearest standard tarp size automatically.
pet Calculators
View all →Dog Food Calculator — Daily Portion by Weight & Life Stage
Calculate your dog's daily food portion in cups or grams using the veterinary RER/DER formula, weight, and life-stage activity level.
Horse Color Calculator — Coat Color Genetics Predictor
Predict horse coat color from genotype: base color, cream, dun, champagne, silver, grey, roan, and spotting patterns, with the Frame Overo lethal warning.
Animal Gestation Calculator — Dog, Cat, Cattle, Goat, Horse
Estimate a due date for dogs, cats, cattle, goats, or horses from the breeding date. Species-specific earliest/expected/latest gestation windows.
Chocolate Toxicity Calculator for Dogs
Estimate theobromine toxicity risk after your dog eats chocolate, by weight and chocolate type. Includes ASPCA Poison Control guidance.
Dog Age Calculator — Human Years by Breed Size
Convert your dog's age to human years using the AVMA breed-size method or the UCSD epigenetic DNA formula. More accurate than the outdated x7 rule.
Puppy Weight Calculator — Predict Adult Dog Weight
Predict your puppy's adult weight from current age and weight using size-category growth curves for toy, medium, large, and giant breeds.
Cat Coat Color Calculator: Kitten Genetics Predictor (Punnett Square)
Predict kitten coat colors from parent genetics using Punnett squares. Covers B, D, O, and A loci — black, chocolate, cinnamon, dilutes, and tortoiseshell.
Fish Tank Stocking Calculator: Inch-per-Gallon, Surface Area & Bioload
Calculate how many fish your aquarium can hold using 3 methods: inch-per-gallon, surface area, and bioload. Fresh and saltwater. 13 preset species.
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