All calculators

Area Calculator

Calculate the area of a rectangle from its length and width, then convert the result between metric and imperial area units.

Concrete Calculator

Estimate concrete for slabs, strip footings, cylindrical columns, post holes, or a combined project with multiple areas.

Flooring & Tile Calculator

Estimate flooring planks, tiles, grout-aware tile layouts, package counts, and combined room or wall areas.

Paint Calculator

Estimate paint for a room, one wall, or multiple walls after subtracting doors and windows, applying coats, coverage, and allowance.

Drywall Calculator

Estimate drywall sheets for a room, one wall, or multiple walls, with optional ceiling area, opening deductions, and waste allowance.

Wallpaper Calculator

Estimate wallpaper rolls for a room, one wall, or multiple walls using openings, roll size, pattern repeat, and waste allowance.

Roofing Calculator

Estimate pitched roof area, shingle bundles, underlayment rolls, and sheathing sheets from roof dimensions, overhang, pitch, and product coverage.

Insulation Calculator

Estimate insulation packages for attics, walls, floors, or combined regions using measured area, openings, waste, and product coverage.

Brick & Block Calculator

Estimate bricks or concrete blocks for one or more walls using unit face size, mortar joint width, openings, and waste allowance.

Mortar Calculator

Estimate wet masonry mortar volume or preblended bags from brick or block quantity, unit dimensions, joint width, fill factor, product yield, and waste.

Gravel Calculator

Estimate gravel, crushed stone, road base, river rock, or sand volume, weight, bags, allowances, and optional cost from area and layer depth.

Mulch & Soil Calculator

Estimate mulch, topsoil, or compost volume, whole bags, allowance, excess, and optional material cost across multiple areas.

Paver & Patio Calculator

Estimate pavers, packs, compacted base, bedding, joint-sand bags, edge restraint, allowances, and optional component costs.

Retaining Wall Calculator

Estimate courses, blocks, caps, aggregate, core fill, drain pipe, user-specified geogrid, and optional material cost.

Stair Calculator

Calculate equal risers, treads, run, angle, stringer length, surface quantities, space differences, and approximate floor opening.

Decking & Deck Material Calculator

Estimate deck boards, reusable cuts, picture-frame borders, joists, rim boards, fasteners, optional railing components, plan-supplied quantities, and material costs.

Fence Material Calculator

Estimate preassembled fence panels or site-built pickets, posts, rails, gates, caps, fasteners, post-hole concrete bags, and optional material cost across multiple fence runs.

Siding Material Calculator

Estimate siding packages or exposed-face pieces from multiple walls and gables, optional opening deductions, waste, housewrap, starter strip, trim stock, and entered material prices.

Lumber & Board Foot Calculator

Build a multi-size lumber list and calculate requested and purchase pieces, board feet, cubic volume, linear length, optional density-based weight, waste, and price by piece or board foot.

Wall Framing Material Calculator

Estimate common, king, jack, cripple and extra studs, plates, user-specified header material, sheathing sheets, fasteners and optional material costs across multiple walls and openings.

Post Hole & Footing Concrete Calculator

Estimate concrete for multiple circular, square and bell-bottom post holes or standalone round and rectangular footings, with embedded-post displacement, waste, bag yield and cost.

Drainage Slope & Fall Calculator

Solve drainage slope, required fall, available run or grade from elevations with mixed units, signed flow direction, ratio, angle, millimeters per meter and inches per foot.

Preliminary HVAC Heating & Cooling Load Estimator

Estimate block-level transmission, infiltration, solar, internal sensible and latent heating/cooling loads from explicit envelope, weather, humidity and occupancy inputs in SI or imperial units.

Rebar Material Calculator

Estimate two-way rebar grids, stock bars, laps, waste, nominal weight and optional cost across multiple areas.

Asphalt & Driveway Material Calculator

Estimate compacted asphalt volume, order weight, allowance, truckloads and optional material cost for multiple paving sections.

French Drain Material Calculator

Estimate excavation, gravel, pipe stock, couplers, slope fall, filter fabric and optional cost for multiple drain runs.

Pipe Volume & Fill Time Calculator

Calculate full-pipe capacity and liquid weight, then solve ideal fill time, required flow and average velocity across multiple segment groups.

Excavation & Earthwork Calculator

Estimate bank, loose, backfill, haul-off and imported earth volumes, truckloads and optional costs across multiple pits and trenches.

Tile Grout Calculator

Estimate grout volume, weight, whole packages and optional cost from tile-joint geometry or manufacturer-stated coverage.

Tile Adhesive & Thinset Calculator

Estimate tile adhesive area, weight, whole packages and cost from manufacturer coverage or an entered application rate.

Self-Leveling Compound Calculator

Estimate self-leveling underlayment volume, whole bags, primer and cost for uniform or sloped fill depths across multiple areas.

Sealant & Caulk Calculator

Estimate joint-sealant volume, cartridges, coverage length, backer rod and optional cost across multiple joint groups.

Masonry Core Fill & Grout Calculator

Estimate CMU core and bond-beam grout volume, bag yield, rebar displacement and cost for multiple walls.

Waterproofing Membrane Calculator

Estimate liquid or sheet waterproofing, primer, seam band, whole packages and cost across multiple surfaces.

Drywall Joint Compound Calculator

Estimate joint compound containers, tape rolls, corner bead, purchase volume and cost for a selected drywall finish level.

Plaster & Stucco Calculator

Estimate base and finish plaster volumes, whole bags, optional lath rolls and cost from verified yield at reference thickness.

Concrete Repair & Resurfacing Calculator

Estimate thin concrete overlays, multiple repair patches, product packages, bonding agent and cost with separate verified yields.

Rainwater Harvesting & Tank Calculator

Estimate roof runoff, first-flush loss, collectable rainwater, tank storage, overflow and simplified non-potable demand across multiple roofs.

Pool Volume, Fill Time & Water Cost Calculator

Estimate capacity, partial fill or drain volume, ideal time and optional water cost for supported pool shapes or combined sections.

Date Difference Calculator

Find the exact calendar difference between two dates in years, months, days, total weeks, days, and hours, with optional inclusive counting.

Business Days Calculator

Count working days between two dates with configurable weekends, custom holidays, inclusive boundaries, and optional work-hour conversion.

Age Calculator

Calculate exact age in calendar years, months, and days, plus completed months, weeks, days, hours, birth weekday, and the next birthday.

Date Add & Subtract Calculator

Add or subtract calendar years, months, weeks, and days from a date with explicit month-end handling and a localized result date.

Work Hours & Pay Calculator

Build a seven-day timesheet, subtract unpaid breaks, handle overnight shifts, and estimate regular hours, overtime hours, and gross pay.

Time Duration Calculator

Calculate exact elapsed time between two zoned date-times, with seconds, breaks, reversed inputs, and daylight-saving changes.

Time Zone Converter

Convert one local date-time to up to four IANA time zones with daylight-saving offsets, date changes, and ambiguity controls.

Countdown Calculator

Create a live, shareable countdown to an exact date-time in any IANA time zone, with stop-at-zero or count-up behavior.

Unix Timestamp Converter

Convert Unix timestamps and zoned date-times in seconds, milliseconds, microseconds, or nanoseconds without losing integer precision.

Loan Payment Calculator

Estimate a fixed-rate installment loan payment, payoff date, total interest, fees, and the effect of extra monthly payments.

Mortgage Calculator

Estimate fixed-rate principal and interest plus property tax, insurance, mortgage insurance, association dues, and extra principal.

Compound Interest Calculator

Project savings growth from an initial balance, recurring contributions, compounding frequency, timing, and optional inflation.

Credit Card Payoff Calculator

Estimate payoff time and interest from a fixed monthly payment, or calculate the payment required for a target payoff period.

Savings Goal Calculator

Calculate the monthly contribution needed to reach a savings target from a current balance, time horizon, rate, and compounding choice.

Retirement Calculator

Project retirement savings, spending needs, funding gaps, monthly contributions, inflation, fees, and conservative-to-optimistic scenarios.

Emergency Fund Calculator

Estimate an emergency savings target, current expense coverage, funding gap, time to goal, or the monthly amount needed by a target date.

Debt Payoff Calculator

Compare debt avalanche and debt snowball plans for up to ten debts, including payoff dates, interest, order, schedules, and CSV export.

Net Worth Calculator

Create a private personal or household balance sheet from categorized assets and liabilities, key ratios, and an optional previous snapshot comparison.

Rent vs. Buy Calculator

Compare renting with buying using mortgage amortization, ownership costs, rent growth, home equity, selling costs, and investing the cash-flow difference.

Home Affordability Calculator

Estimate a prudent home-price ceiling from income, recurring debt, cash available after reserves, mortgage terms, closing costs, and ongoing ownership expenses.

Mortgage Refinance Calculator

Compare keeping your current fixed-rate mortgage with refinancing, including closing costs, financed fees, points, credits, cash-out, break-even timing, and lifetime cost.

HELOC Calculator

Estimate HELOC draw-period and repayment-period payments, payment shock, variable-rate stress scenarios, interest, fees, available credit, and combined loan-to-value.

Debt Consolidation Calculator

Compare multiple fixed-payment debts with one consolidation loan, including origination fees, financed or deducted costs, payment change, payoff time, break-even timing, and lifetime cost.

Student Loan Repayment Calculator

Plan multiple student loans through a grace or deferment period, interest capitalization, a fixed repayment term, and strategic extra payments.

Auto Loan Calculator

Estimate amount financed, monthly payment, interest, tax, fees, trade-in equity, and the effect of extra auto-loan payments.

Debt-to-Income Ratio Calculator

Calculate housing-payment and total debt-to-income ratios from gross monthly income and recurring monthly obligations.

Monthly Budget Calculator

Normalize recurring income and expenses into a monthly budget, then estimate cash-flow surplus, savings rate, debt-payment ratio, and annual balance.

Percentage Calculator

Calculate a percentage of a number, find one value as a percentage of another, measure percentage change, or adjust a value by a percentage.

Discount Calculator

Calculate the final price, savings, effective discount, optional sequential discount, coupon, and tax.

Sales Tax & VAT Calculator

Add sales tax or VAT to a net price, or extract the tax and net amount from a tax-inclusive total.

Tip & Bill Split Calculator

Calculate a tip, total bill, equal per-person share, and optional round-up adjustment.

Unit Converter

Convert length, area, volume, mass, temperature, and speed with explicit units and adjustable display precision.

Unit Price Calculator

Compare two package prices across counts, mass, volume, or length and identify the lower normalized unit price.

Fuel Cost Calculator

Estimate trip fuel and cost using L/100 km, km/L, U.S. MPG, or Imperial MPG with clearly separated gallon definitions.

Electricity Cost Calculator

Estimate device energy use and cost by power, quantity, daily hours, days, and a user-entered price per kilowatt-hour.

Speed, Distance & Time Calculator

Calculate speed, distance, or travel time from the other two values with metric, imperial, nautical, and compound time units.

Running Pace Calculator

Calculate running pace, finish time, or distance with kilometer and mile pacing, race presets, and an even-pace split table.

Heart Rate Zones Calculator

Estimate five exercise heart-rate zones with maximum-heart-rate or heart-rate-reserve methods and clear safety guidance.

Race Time Predictor

Project an equivalent finish time from a recent race with the Riegel model, common race presets, pace conversion, and comparison table.

Steps and Distance Calculator

Convert between steps, distance, and measured step length with metric and imperial units plus optional cadence-based time.

Running Calorie Calculator

Estimate gross and net activity calories from body weight, distance, duration, pace-derived METs, or a chosen activity MET.

VO₂ Max Estimate Calculator

Estimate aerobic capacity with a Cooper 12-minute run, Rockport one-mile walk, or maximum-to-resting heart-rate ratio.

Training Pace Zones Calculator

Turn a recent race performance into easy, marathon, threshold, interval, and repetition training pace ranges.

Running Cadence and Step Length Calculator

Solve running cadence, distance per step, or pace and analyze steps, two-step strides, timing, and a same-speed cadence scenario.

BMI & Healthy Weight Calculator

Calculate adult BMI, weight category, and the BMI-based healthy-weight range for a given height in metric or imperial units.

BMR & TDEE Calculator

Estimate resting energy, maintenance calories, goal-adjusted calories, and activity-level comparisons with transparent equations.

Body Fat Percentage Calculator

Estimate body-fat percentage, fat mass, lean mass, BMI, and waist-to-height ratio from circumference measurements.

Macronutrient Calculator

Convert a daily calorie target into protein, carbohydrate, fat, per-meal amounts, and an adult AMDR comparison.

One-Rep Max Calculator

Estimate one-repetition maximum with seven equations, compare model range, and build rounded percentage training loads.

Barbell Plate Calculator

Build a symmetrical barbell from your actual plate inventory and compare exact, nearest-under, and nearest-over plans.

Strength Training Volume Calculator

Track multiple exercises and set groups, separate warm-ups, calculate external volume load, intensity, and prior-session change.

Activity Calories Calculator

Combine activities and estimate gross and net energy expenditure from duration, body weight, and 2024 Compendium MET values.

RPE and RIR Load Calculator

Convert RPE and repetitions in reserve, estimate percentage of one-rep max, calculate a rounded target load, or estimate 1RM from a completed set.

Strength Warm-Up Set Calculator

Build a rounded ramp-up sequence from a working load or percentage of 1RM with preset and custom warm-up schemes.

Progressive Overload Planner

Build a week-by-week arithmetic strength progression using fixed load, percentage increases, or double progression with optional deload weeks.

Powerlifting Total and IPF GL Score Calculator

Record three attempts per lift, calculate a valid total, body-weight multiple and official IPF GL points.

Cycling FTP & Power Zones Calculator

Enter a known FTP or estimate it from a field test, then calculate seven cycling power zones, sweet spot power, and watts per kilogram.

Bike Gear Ratio, Cadence & Speed Calculator

Compare chainring and sprocket combinations, rollout, gear inches, speed at cadence, required cadence, total range, and near-duplicate gears.

Cycling Power-to-Weight Calculator

Calculate watts per kilogram across five cycling durations, compare two profiles, and reverse-calculate target FTP power or mathematical body mass.

Cycling Power, Grade & Speed Calculator

Estimate steady cycling speed from power or required power from speed using grade, mass, distance, wind, rolling resistance, aerodynamics, and drivetrain loss.

Cycling Training Load Calculator

Calculate intensity factor, variability index, mechanical work, TSS-compatible ride load, load per hour, and projected weekly load from FTP and power data.

Cycling Critical Power & W′ Calculator

Fit critical power and W prime from two to five maximal cycling efforts, compare two linearized models, inspect fit error, and predict power or duration.

Cycling Pace & Split Planner

Solve cycling time or average speed, subtract stopped time, and generate distance or lap splits using even, negative, or positive pacing.

Cycling Climb & VAM Calculator

Analyze one or more cycling climbs with route distance, elevation gain, time and repetitions to calculate exact average grade, VAM, ascent speed and totals.

Cycling Route Power & Time Planner

Plan up to twelve cycling route segments with distance, grade, target power, wind and rolling resistance to estimate speed, time, work and elevation.

Cycling Interval & W′ Balance Calculator

Build repeated intervals and simulate second-by-second W′ depletion above critical power and adjustable recovery below it.

Cycling Fueling & Energy Planner

Estimate energy from power or manual calories, set a carbohydrate target, combine drinks and food, and fill the remainder with whole gels.

Cycling Sweat Rate & Hydration Calculator

Calculate sweat loss and hourly sweat rate from pre/post weight, fluid intake, urine and duration, then scale a user-selected replacement plan.

Cycling Tire Pressure Calculator

Estimate separate front and rear bicycle tire pressures from total system weight, load split, measured tire width, surface, casing and tube setup, with user-entered tire and rim limits.

Bike Fit Frame & Saddle Calculator

Estimate a frame-size range, saddle-height starting point, pedal-axis comparison, standover clearance and reach profile from body measurements and bicycle type.

Bike Chain Length Calculator

Estimate bicycle chain length from chainstay and largest gears, add large-cog or custom allowance, account for suspension growth, and compare with the packaged chain.

Bicycle Spoke Length Calculator

Calculate independent left and right bicycle spoke lengths from measured ERD, hub flange geometry, lacing crosses, rim offset and spoke-hole style, with stock-length rounding.

Bicycle Wheel & Tire Size Calculator

Calculate bicycle wheel diameter and circumference from ETRTO dimensions, use measured rollout, check bike-computer error and compare another tire size.

Bike Suspension Sag Calculator

Calculate fork or rear-shock target sag, compare measured displacement and estimate one cautious air-pressure or coil-rate adjustment.

Bike Frame Geometry Comparison Calculator

Compare two bicycle frames by stack, reach, wheelbase, rear-center, angles, BB drop and calculated steering trail.

Tubeless Tire Sealant Calculator

Estimate sealant for initial bicycle tubeless setup or top-ups, then calculate complete bottles, leftover and optional cost.

Bike Stem, Spacer & Handlebar Position Calculator

Compare two bicycle cockpit positions from frame stack and reach, head angle, spacers, stem and handlebar dimensions, then search available setup combinations.

Mountain Bike Coil Spring Rate Calculator

Estimate a rear-shock coil spring starting rate from ready-to-ride weight, rear load bias, wheel travel, shock stroke, target sag and preload.

Bicycle Crank Length & Pedal Motion Calculator

Compare two crank lengths by pedal circle, pedal speed, tangential force, saddle-height reference and top- or bottom-of-stroke clearance.

Bicycle Spoke Tension Balance Analyzer

Analyze measured left- and right-side spoke tensions, relative uniformity, target ranges, side averages and individual outliers.

Handwriting Math Calculator

Write a complete expression with a mouse, touchscreen or stylus, automatically segment common mathematical symbols, review candidates and calculate safely.