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Search 285 free calculators for math homework, grades, statistics, conversions, dates, and formulas. No signup, no clutter, just focused tools with steps and examples.

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Fast starting points for the questions students and families ask most.

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Scientific CalculatorFull scientific calculator with sin, cos, tan, log, ln, sqrt, exponents, pi, and e.

Percentage CalculatorCalculate percent of a number, part-to-whole percentages, percent change, missing wholes, and reverse percent changes.

Slope CalculatorFind slope from two points or solve a missing coordinate from a known slope. Includes equations, intercepts, grade, graph, and step-by-step work.

Tip CalculatorCalculate tip, tax, rounded totals, and per-person split, or find the tip percentage from a known tip amount.

Discount CalculatorCalculate sale price, stacked discounts, original price before a discount, or the discount percent between two prices.

BMI CalculatorCalculate adult BMI from metric or imperial measurements, see CDC-style categories, healthy weight range, and target BMI weight.

Age CalculatorCalculate exact age or date difference in years, months, days, total days, weeks, hours, weekdays, and next birthday countdown.

Mortgage CalculatorEstimate mortgage payment, PITI, PMI, total interest, first-month amortization, or reverse-solve home affordability from a target payment.

Loan CalculatorCalculate fixed-rate loan payment, total interest, payoff time with extra payments, or reverse-solve loan amount from a monthly payment.

Compound Interest CalculatorCalculate investment growth with compound interest, regular contributions, inflation adjustment, or reverse-solve the monthly contribution needed for a target.

GPA CalculatorCalculate semester GPA, update cumulative GPA, or find the future grade average needed to reach a target GPA.

Grade CalculatorCalculate a class grade from points earned, points possible, extra credit, and a target percentage.

Final Grade CalculatorFind the score you need on a final exam or project your course grade from a known final score.

Test Grade CalculatorCalculate a test percentage and letter grade from points earned, points missed, or a target grade.

Weighted Grade CalculatorCalculate a weighted course grade from category scores and weights, or find the score needed on remaining weighted work.

Average After Next Score With Drop CalculatorProject your grade average after adding one known next score and then dropping the lowest equal-weight score.

Average After Remaining Scores CalculatorProject your final equal-weight grade average after adding several known or planned remaining quiz, test, homework, or assignment scores.

Average After Remaining Scores With Drop CalculatorProject your final grade average after adding several known remaining scores and then dropping the lowest equal-weight scores.

Assignment Weight Impact CalculatorEstimate how one upcoming assignment with a direct course weight changes your current course grade.

Class Average After Next Score CalculatorProject your class or quiz average after adding one known equal-weight next score, then compare it with a target average.

Grade Target With Assignment CalculatorFind the score needed on one direct-weight assignment to reach a target course grade.

Grade Percentage CalculatorConvert points earned or points missed into a grade percentage, decimal, simplified score fraction, and letter grade.

Grade Drop CalculatorCalculate a grade average after dropping the lowest quiz, test, homework, or assignment scores.

Late Penalty Grade CalculatorCalculate the counted grade after a late-work penalty is applied to an assignment, quiz, test, or project score.

Missing Assignment Impact CalculatorSee how one missing zero-score assignment affects a point-based grade and how makeup or partial credit changes the result.

Makeup Points Needed CalculatorSolve how many makeup or partial-credit points you need to reach a target grade in a point-based class.

Next Score Needed CalculatorSolve the score you need on the next equal-weight quiz, test, homework, or assignment to reach a target average.

Remaining Scores Average Needed CalculatorFind the average you need across several remaining equal-weight quiz, test, homework, or assignment scores to reach a target grade average.

Remaining Scores Average Needed With Drop CalculatorFind the average needed across several remaining equal-weight scores when your class drops the lowest score or scores.

Retake Grade CalculatorCalculate how a quiz, test, homework, or assignment retake changes your grade average when one earlier score is replaced.

Retake Score Cap CalculatorModel how a capped retake score changes your average when one earlier score can be replaced.

Retake Score Needed CalculatorSolve the retake score needed to reach a target average when one earlier quiz, test, or assignment score can be replaced.

Score Needed With Dropped Lowest CalculatorFind the next score needed to reach a target average when your class drops the lowest equal-weight score.

Average CalculatorCalculate arithmetic, weighted, geometric, or harmonic averages from a list of numbers with steps and summary statistics.

Mean Median Mode Range CalculatorFind mean, median, mode, range, count, sum, minimum, and maximum for a list of numbers with sorted values and steps.

Fraction CalculatorAdd, subtract, multiply, divide, simplify, compare, or convert decimals to fractions with steps and visual fraction bars.

Standard Deviation CalculatorCalculate sample or population standard deviation, variance, mean, and z-score-ready summary statistics from a data list.

67 CalculatorEnter any number, equation, tax situation, homework panic, or suspicious life problem. The answer is always 67.

Pixel Graphing CalculatorA nostalgic green-LCD calculator skin that solves simple arithmetic and turns the result into a chunky classroom demake card.

Retro Desktop CalculatorA gray-bevel desktop calculator throwback with tidy arithmetic, title-bar energy, and peak old-computer charm.

Nice Number CalculatorCheck whether a number hits classic internet-number energy like 69, 420, 1337, 404, or pi-adjacent calculator lore.

Skin Budget CalculatorPlan game skin purchases, pass costs, taxes, and a monthly budget before the phrase this is the last one gets tested again.

Loot Box Expected Value CalculatorCalculate expected value, expected net, and boxes-per-drop math for a probability-based loot box or mystery pack scenario.

Minecraft Stack CalculatorConvert item counts into stacks, leftovers, shulker boxes, and chest space for Minecraft-style inventory planning.

Can I Afford This CalculatorCompare a purchase price with available fun money, recurring commitments, and a playful guilt multiplier before buying.

Vibe Check CalculatorCalculate a transparent vibe score from sleep, hydration, playlist confidence, outfit confidence, deadline pressure, and social battery.

Robux to USD CalculatorEstimate Robux purchase cost or convert a dollar budget into an approximate Robux amount with clear Roblox economy notes.

Roblox Tax CalculatorEstimate marketplace fees, creator Robux after tax, and optional DevEx USD value for Roblox game pass or item sales.

Creator Earnings SimulatorEstimate YouTube RPM revenue and Twitch subscription revenue with playful what-if defaults and clear simulator disclaimers.

TikTok Engagement Rate CalculatorCalculate TikTok engagement rate from views, likes, comments, shares, and saves with a clean rating label.

K/D Ratio CalculatorFind how many consecutive kills you need to reach a target K/D ratio and what your K/D becomes after extra kills.

Minecraft Nether Portal CalculatorConvert Minecraft Overworld and Nether X/Z coordinates by the 8:1 portal scale so you can link portals without guessing.

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The library is organized around the way people search: grades, money, core math, science, construction, dates, health, conversion, and statistics.

Finance & Money

Mortgage, loan, interest, tips, and money math.

30 calculators

Health & Fitness

BMI, BMR, body fat, and wellness calculators.

17 calculators

Math

Percentage, fraction, ratio, and core math tools.

44 calculators

Conversions

Convert length, weight, temperature, and more.

36 calculators

Everyday

Tip, gas, discount, and daily-life calculators.

3 calculators

Education

GPA, grade needed, and study calculators.

23 calculators

Time & Date

Age, date difference, and time calculators.

7 calculators

Statistics

Mean, median, standard deviation, and probability.

24 calculators

Pop Culture

Gaming, creator, and internet math calculators.

35 calculators

Science

Physics, chemistry, lab, and classroom science formulas.

34 calculators

Construction & Materials

Concrete, paint, flooring, roofing, and project material estimates.

32 calculators

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