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Fraction Calculator — Add, Subtract, Multiply, Divide with Steps

Add, subtract, multiply, divide fractions — auto-reduced, with steps, mixed ⇄ improper ⇄ decimal — browser-only

  • Runs locally
  • Category Calculator
  • Best for Getting a realistic range before a purchase, plan, workout, or schedule decision.

Type an integer (3), a fraction (3/4), or a mixed number (1 1/2).

Result
5/6
Improper: 5/6Decimal: 0.83

The bar marks the repeating block.

Show result as
How it reduces
  1. Bring to a common denominator: 1/2 + 1/3 = 1×3/2×3 + 1×2/3×2
  2. = 5/6
  3. Already in lowest terms.

What this tool does

A fraction calculator that does exact rational arithmetic in your browser — no rounding, no float drift. Type two values in any of three forms (a whole number like 3, a simple fraction like 3/4, or a mixed number like 1 1/2) and pick +, −, ×, or ÷. The answer comes back already reduced to lowest terms with the sign normalised onto the numerator, and a step-by-step breakdown shows exactly how it got there: how the common denominator was found, where the cross-multiply happened, and which gcd it divided by to reduce. Every result is shown four ways at once — improper fraction, mixed number, and decimal — so you never have to run a second tool to convert. The decimal view does real long division and flags repeating decimals with an overline (1/3 → 0.3̅, 1/7 → 0.142857‾), not a rounded-off float. Divide-by-zero and a zero denominator give a clear message instead of NaN. The operator and both operands live in the URL, so a worked example you build is one copy-paste away from a classmate or a worksheet.

Tool details

Input
Text + Numbers
The page exposes text boxes, numeric controls, file pickers, or structured inputs depending on the tool.
Output
Live result + Copy
The result area focuses on usable output, with copy, download, or preview actions when supported.
Privacy
Browser-side processing
The main tool logic does not call an external API, so inputs normally stay in the current tab.
Save / share
Shareable URL state
Key settings are encoded in the URL so another person can reopen the same setup.
Performance budget
Initial JS <= 9 KB
No WASM budget is declared, keeping the tool quick to open on mobile.
Best fit
Calculator · Student
Category and role tags drive related tools, internal links, and quick fit checks.

How to use

  1. 1. Input

    Paste or drop your content into the tool panel.

  2. 2. Process

    Click the button. All processing is local in your browser.

  3. 3. Copy / Download

    Copy the result or download to disk in one click.

How Fraction Calculator fits into your work

Use it for fast estimates, comparisons, and planning numbers before you make the final call.

Calculation jobs

  • Getting a realistic range before a purchase, plan, workout, or schedule decision.
  • Comparing scenarios by changing one input at a time.
  • Turning rough assumptions into a number you can discuss.

Calculation checks

  • Double-check units, dates, rates, and rounding assumptions.
  • Treat health, finance, tax, and legal outputs as planning aids, not professional advice.
  • Save the inputs that produced an important result so you can reproduce it later.

Good next steps

These links move the current task into a more complete workflow.

  1. 1 Scientific Calculator Scientific calculator — sin / cos / log / sqrt / power, with full keyboard input + history, deg/rad mode. Open
  2. 2 Percentage Calculator 5 common percentage calculations — "x% of y", "x is what% of y", percentage change, increase/decrease — instant, browser-only Open
  3. 3 Statistics Basic Calculator Basic statistics calculator — mean/median/mode/variance/std-dev/quartiles/range/IQR/skewness/kurtosis + histogram + box plot, paste any numbers. Open

Real-world use cases

  • Check a kid's fractions homework without redoing it by hand

    A 5th-grader brings home "1/2 + 1/3 + 1/6" and a worksheet that wants the answer in lowest terms. Type 1/2 + 1/3 first, read 5/6, then add 1/6 to that result for the final 1. The step view spells out the common denominator (6) and the gcd reduction, so when the kid asks "but why isn't it 2/5?" you point at the common-denominator line instead of waving your hands. You confirm the answer in seconds and you have the actual working to explain.

  • Build a worked example to share in a class group chat

    You're a teacher prepping a quick "do this one tonight" problem for the parents' WeChat or Remind group. Set up 3/4 ÷ 2/3, screenshot or just copy the URL — the link reproduces the exact problem AND the flip-and-multiply steps when a parent opens it on their phone. No PDF, no login, works on any device, and the bilingual labels mean a non-English-first parent still follows the math.

  • Convert a recipe's mixed-number measurement to a decimal

    A recipe says 1 3/4 cups but your digital kitchen scale and the doubling math both want decimals. Type 1 3/4, read 1.75 in the decimal row, double it mentally to 3.5. Going the other way works too: type 2.5 worth of fractions like 5/2 and read the mixed number 2 1/2 for the measuring-cup version. One box, both mental models.

  • Sanity-check a fraction that a spreadsheet rounded

    Excel shows 0.3333333 for a cell and you suspect it's really 1/3 but can't be sure from the rounded display. Type 1/3 here and the decimal row shows 0.3 with an overline — confirming it's the exact repeating third, not 0.3333333 truncated. Do the same for 1/7 vs 0.142857 to tell a clean ratio apart from a messy one before you trust a formula.

  • Teach reciprocals by watching division flip the fraction

    Reciprocals click for students the moment they SEE the flip. Set the operator to ÷, put 1 in box A and any fraction in box B (say 3/8), and the step "flip B and multiply" turns 1 ÷ 3/8 into 1 × 8/3 = 8/3. Change B to 8/3 and watch it flip back to 3/8. Two clicks make the "reciprocal = the flipped fraction" rule concrete instead of memorised.

Common pitfalls

  • Adding straight across: 1/2 + 1/3 is NOT 2/5. You can't add numerators and denominators independently — you need a common denominator first, so the answer is 5/6. The step view shows the common-denominator stage so this stops being a mystery.

  • Forgetting that ÷ flips the SECOND fraction. `1/2 ÷ 1/4` is `1/2 × 4/1 = 2`, not `1/8`. People who flip the first fraction instead get the reciprocal of the right answer. The "flip B and multiply" step makes the order explicit.

  • Typing a mixed number without the space — `11/2` is eleven halves (5.5), while `1 1/2` is one and a half (1.5). They're different numbers. If a result looks about ten times too big, check whether a space went missing.

Privacy

All the arithmetic — gcd reduction, common denominators, long division for the decimal — is plain JavaScript running in your browser tab. Nothing you type is sent anywhere, logged, or measured. The one thing to know: the operator and both fractions are written into the page URL (e.g. `?a=1/2&op=add&b=1/3`) so a "share this calculation" link reproduces your exact problem for whoever opens it. The numbers are not sensitive, but if you ever pasted something private into a box, copy the answer manually rather than sharing the link.

FAQ

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Made by Toolora · 100% client-side · Updated 2026-06-13