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View all →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.
engineering Calculators
View all →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 →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 →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 →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 →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 →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.
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 →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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