New and Updated View all →
Grades & School All 7 →
- Final Grade CalculatorWhat you need on the final, for every letter grade, with the working shown.
- GPA CalculatorTerm and cumulative GPA on the 4.0 scale, with quality points and the working shown.
- Grade CalculatorYour current course grade from assignment scores and weights, with the letter and the working.
- High School GPA CalculatorWeighted and unweighted GPA together, with honors and AP bumps and what they are actually worth.
- Semester Grade CalculatorQuarter grades plus the semester final, or what you need on that final.
- Test Grade CalculatorPoints or questions wrong into a percentage, a letter, and a grading chart for your test.
- Weighted Grade CalculatorCombine category grades by syllabus weight, and see which category is worth your time.
Math All 44 →
- Percentage CalculatorPercent of a number, percent-of, and percent change in one tool.
- Fraction CalculatorAdd, subtract, multiply, or divide fractions, simplified automatically.
- Derivative CalculatorStep-by-step derivatives of polynomials, trig, exponentials and logs, every rule shown.
- Solve for X CalculatorType an equation, get every solution with the work shown.
- Quadratic Formula CalculatorSolve ax² + bx + c = 0: real, repeated, or complex roots.
- Law of Cosines CalculatorSolve SSS and SAS triangles, with every step shown.
- Average CalculatorMean, median, sum, min, max, and range from any list of numbers.
- Order of Operations CalculatorEvery step narrated, plus both honest answers to viral bait like 8/2(2+2).
- Long Division CalculatorLong division worked one digit at a time, with the full bracket layout.
Science All 19 →
- Molar Mass CalculatorMolar mass and percent composition from any formula, with honest digits.
- Molarity CalculatorMolarity, molality, normality and percent, solved from your formula.
- Dilution CalculatorC1V1 = C2V2 with the recipe, plus serial dilutions done honestly.
- Half-Life CalculatorDecay in both directions, 13 isotopes, and honest radiocarbon dating.
- Gas Law CalculatorAll six gas laws, with the work shown and the kelvin trap priced.
- Kinetic Energy CalculatorKinetic and potential energy, and why double the speed is four times the energy.
- Acceleration CalculatorAll five kinematics quantities from any three, plus the answer in g.
- Wavelength CalculatorFrequency to wavelength for light, sound and anything else that waves.
Statistics All 22 →
- Standard Deviation CalculatorSample or population standard deviation from any list of numbers.
- Sample Size CalculatorHow many responses you need, and why the population barely matters.
- Hypergeometric CalculatorExact odds for drawing without replacement, every tail shown.
- Binomial Distribution CalculatorExact odds over a fixed number of independent tries.
- Z-Score CalculatorHow many standard deviations from the mean, with percentile.
- P-Value CalculatorP-value from a z-score: two-tailed, left-tailed, or right-tailed.
- Confidence Interval CalculatorConfidence interval and margin of error for a sample mean.
- Normal Distribution CalculatorBell curve probability: below, above, or between any values.
- Probability CalculatorSingle events, and/or combinations, and at-least-once odds with steps.
- Combination CalculatornCr and nPr with step-by-step work, plus which one you actually need.
Finance & Money All 97 →
- Mortgage CalculatorMonthly payment with taxes, insurance, and HOA, plus lifetime interest.
- Compound Interest CalculatorWatch savings grow with contributions, year by year.
- Income Tax Calculator2026 federal tax, refund estimate, and a bracket-by-bracket breakdown.
- Credit Utilization CalculatorWhat your card will report, and which date actually matters.
- Roth 401(k) CalculatorRoth or traditional, compared on what you get to spend.
- Take-Home Pay CalculatorYour 2026 net paycheck with federal tax, FICA, and 401(k) itemized.
- Loan CalculatorMonthly payment, total interest, and a year-by-year payoff schedule.
- Rent vs Buy CalculatorBoth paths priced to the dollar: net costs, break-even year, and a coin-flip call.
- Retirement Withdrawal CalculatorFind out how long your retirement savings will really last.
- Amortization CalculatorThe full payment-by-payment schedule, payoff date, and extra-payment savings.
Business & Marketing All 34 →
- Margin CalculatorGross, operating, and net margin as one ladder, plus target pricing.
- Markup vs Margin CalculatorSame dollars, two denominators: both percentages side by side.
- Break-Even CalculatorUnits and revenue to cover the bills, plus your margin of safety.
- Price Elasticity of Demand CalculatorElasticity by the midpoint method, plus the profit answer.
- ROAS CalculatorROAS plus the break-even ROAS your margin sets, and the real profit.
- Customer Lifetime Value CalculatorDiscounted LTV on a profit basis, plus your LTV to CAC ratio.
- Invoice CalculatorLine items, discount, tax, and balance due, with the due date from your terms.
- Mileage Reimbursement Calculator2026 IRS rates including the July change, split-year math, taxable excess.
- CPA CalculatorCost per acquisition against the max CPA your margin can afford.
Health & Fitness All 18 →
- BMI CalculatorBody mass index with your healthy weight range.
- TDEE CalculatorYour daily calorie burn, plus cut and bulk targets.
- Calorie CalculatorYour daily calorie target for losing, maintaining, or gaining weight.
- BMR CalculatorCalories you burn at complete rest, with three formulas compared.
- Due Date CalculatorEstimated due date from LMP, conception, or IVF, plus milestone dates.
- Macro CalculatorSplit your calories into protein, carb, and fat grams.
- Sleep CalculatorBedtimes and alarm times that land between 90-minute sleep cycles.
- One Rep Max CalculatorEstimate your 1RM from any rep set, with a %1RM chart.
DIY & Trades All 26 →
- Voltage Drop CalculatorVoltage drop, max run length, and the wire size that actually passes.
- Ohms Law CalculatorThe full power wheel: any two of volts, amps, ohms and watts.
- Watts to Amps CalculatorWatts and amps both ways, with power factor taken seriously.
- Concrete CalculatorCubic yards and bag counts for slabs, footings, and columns.
- Square Footage CalculatorAdd up to three shapes, get total area and project cost.
- Paint CalculatorGallons and quarts of paint for any room, doors and windows deducted.
- Tile CalculatorHow many tiles and boxes to buy, with the right waste factor for your layout.
- Mulch CalculatorYards and bags of mulch at your depth, plus bags-vs-bulk cost.
Cooking & Kitchen All 9 →
- BBQ Meat CalculatorHow much meat to buy for a BBQ, in raw pounds, after the cook takes its half.
- Butter ConverterSticks, cups, tablespoons, ounces, grams: convert butter any direction, fractions included.
- Cake Serving CalculatorA real serving count for any cake, in both the wedding and party slice standards.
- Cooking Measurement ConverterCups, tablespoons, teaspoons, fl oz, ml, liters: any unit to any other.
- Cups to Grams ConverterCups to grams, by ingredient: flour, sugar, butter, honey and more.
- Oven Temperature ConverterFahrenheit, Celsius, gas mark, and the fan adjustment, all from one number.
- Pan Size ConverterSwap baking pans and know exactly how the batter and bake time change.
- Recipe ScalerResize a recipe to any serving count, with kitchen-friendly fractions.
- Turkey Cooking Time CalculatorRoasting time, plus the thawing days nobody plans for.
Unit Conversions All 20 →
- CM to Feet ConverterCentimetres to feet and inches, said the way people say it.
- Ounces to Cups ConverterFluid ounces are exact. Weight ounces depend on the ingredient.
- Grams to Ounces ConverterExact gram to ounce conversion, plus the troy ounce trap.
- Liters to Gallons ConverterBoth gallons every time, because they differ by twenty percent.
- Square Feet to Acres ConverterSquare feet to acres, plus what that plot actually looks like.
- MM to Inches ConverterMM to inches: decimal and nearest 16th, with the rounding shown.
- KG to Lbs Converterkg to lbs with decimal and lb-oz results, plus a chart to 100 kg.
- Meters to Feet ConverterMeters to feet with decimal and feet-inches results, plus a chart to 100 m.
- Cups to Grams ConverterCups to grams, by ingredient: flour, sugar, butter, honey and more.
Tech & Innovation All 24 →
- EV Savings CalculatorGas vs electric: yearly fuel savings, cost per mile, and honest CO2 math.
- EV Charging Time CalculatorHow long a charge really takes: losses and the 80 percent taper counted.
- Data Center Power CalculatorMegawatts, dollars, and CO2: what it actually takes to run a data center.
- GPU Cluster Power CalculatorFrom one 4090 to 100,000 H100s: megawatts, power bills, and CO2, honestly.
- AI Energy CalculatorWhat your AI chatbot habit costs in energy: an honest, cited low-to-high range.
- LLM API Cost CalculatorPrice your monthly GPT, Claude & Gemini API bill by tokens and request volume.
- RAID CalculatorUsable space and honest fault tolerance for RAID 0, 1, 5, 6, 10, and JBOD.
- Space Travel Time CalculatorThe Moon, Mars, or Proxima at any speed, and the 1 g flip and burn, honestly.
Time & Date All 9 →
- Age CalculatorExact age in years, months and days, with the month-end and leap-year cases handled honestly.
- Date CalculatorDays between two dates, or any date plus or minus N days.
- Road Trip CalculatorGoogle's ETA assumes you never stop. Your crew disagrees. Get the real arrival time.
- Shift CalculatorHow long is your shift and what does it pay, differential and all.
- Sleep CalculatorBedtimes and alarm times that land between 90-minute sleep cycles.
- Time CalculatorAdd and subtract hours, minutes and seconds, with the working and the decimal hours shown.
- Time Card CalculatorWeekly hours from your punches: breaks, overtime, and gross pay.
- Time Duration CalculatorThe time difference between two moments, broken down and totalled in every unit.
- Work Hours CalculatorOne day of work, from punches to payroll decimal, breaks deducted.
Fun & Curiosities All 25 →
- Snow Day CalculatorThe odds school closes tomorrow. For fun, hope, and homework avoidance.
- Dice RollerRoll up to 10 dice, d4 through d20, with totals and session history.
- Random Number GeneratorPick random numbers in any range, with or without repeats.
- Dog Years CalculatorYour dog's real human age. Spoiler: it's not age times 7.
- Odds CalculatorConvert American, decimal, and fractional odds, and see the vig hiding in the price.
- Loot Drop CalculatorAny drop rate into odds within N tries, and the cost of certainty.
- MTG Opening Hand CalculatorExact odds of drawing your card: opener, by turn, and mulligans.
- MTG Manabase CalculatorHow many sources your spell actually needs, computed not quoted.
- NFL Win Probability CalculatorPoint spread in, outright win probability out, with the vig stripped away.