Calculators that show their working.
Type your numbers in any unit, see every step of the answer, and convert the result. Everything is worked out in your browser: nothing you type is sent to a server.
Most used
- Concrete calculatorCubic yards and 40, 60 or 80 lb bags for slabs, footings and round columns.
- Mortgage calculatorMonthly payment with tax, insurance and PMI, plus the amortization schedule.
- Loan calculatorMonthly payment, payoff time or interest rate for any fixed-rate loan.
- Gravel calculatorCubic yards and tons of gravel, crushed stone or sand for any area and depth.
- Compound interest calculatorSavings growth with compounding and monthly deposits.
- Square footage calculatorSquare feet for rooms, L-shapes, circles and triangles, with cost.
- Paint calculatorGallons and quarts for a room’s walls and ceiling, by coats and coverage.
- Mulch calculatorCubic yards or 2 and 3 cu ft bags of mulch for any bed shape and depth.
- Auto loan calculatorMonthly car payment with sales tax, fees and trade-in.
- Tile calculatorTiles and boxes for a floor or wall, counting grout joints and cuts.
- Stair calculatorRisers, treads, run and stringer length from the total rise.
- Roofing calculatorRoof area, squares and shingle bundles from the footprint and pitch.
Browse by category
- FinanceLoans, mortgages, savings, investing and business math.67 calculators
- BusinessPricing, break-even, payroll costs and small-business metrics.13 calculators
- Health & fitnessBody measurements, nutrition, training, sports stats and pregnancy dates.29 calculators
- Math & statisticsArithmetic, algebra, geometry and statistics, with the working shown.49 calculators
- Home & DIYMaterials for building, remodeling and repair jobs.45 calculators
- Garden & homesteadSoil, fertilizer, watering, planting, livestock feed and firewood.17 calculators
- Cooking & bakingRecipe scaling, baker’s percentages, conversions and ratios.11 calculators
- EverydayDates, time, school, travel, conversions and handy tools.31 calculators
- Science & engineeringElectricity, chemistry, physics and weather.32 calculators
- CraftsKnitting, quilting, sewing, resin, candles and soap.13 calculators
- Hobbies & techPhotography, electronics, radio, 3D printing, aquariums, music and astronomy.26 calculators
How GlenCalc works
- Shows its working. Each answer comes with the steps, using your own numbers.
- Private. Worked out in your browser. No accounts, no cookies, no trackers.
- Any unit. Type feet and inches, fractions or meters, and convert the answer to the unit you need.
- No artificial limits. Unusual numbers get a warning, not a refusal.
- Cited and tested. Figures come from manufacturers and standards, listed on each page, and worked examples are checked by automated tests.