LazyTools

🔒 Every tool runs in your browser — the files and values you enter are never uploaded to any server. How it works

Mathematics Tools

Calculators that compute exactly — true fractions, arbitrary-precision integers, simplified radicals — and show their working step by step. No floating-point rounding, no "0.9999999999", and nothing you type leaves your browser.

Exact math, with the steps

Most calculators quietly round; these don't. Fractions are added and simplified exactly with the steps shown, repeating decimals convert back to exact fractions, primality uses Miller–Rabin, quadratics keep radical roots, and combinatorics and exponents run at BigInt scale, so 2¹⁰⁰ is digit-for-digit correct. Where a topic has a method — long division, synthetic division, completing the square — the working is laid out, not hidden.

That makes these useful for learning as well as answers, and it all runs in your browser: private, instant and offline. For applied number-crunching see Calculators, Statistics and Finance.

Frequently asked questions

What makes these different from other math calculator sites?

Exactness. These tools compute with arbitrary-precision integers and true rational arithmetic — fractions stay fractions, roots come out in simplified radical form like (3 + √89)/2, and 1000! is produced digit-perfect. Ordinary calculators (and spreadsheet formulas) work in floating point, which silently rounds past 15–17 significant digits and turns 1/3 + 2/3 into 0.9999999999999999.

Why not just ask an AI chatbot?

Language models are notoriously unreliable at arithmetic — they generate plausible-looking numbers rather than computing them, and you can't tell a right answer from a confident wrong one. These calculators run the actual algorithms (Euclid, Miller–Rabin, the quadratic formula) and show the working, so the answer is checkable, not just believable.

Do the tools show the steps?

Where steps are the point, yes — the fraction calculator shows the common-denominator working, the GCD calculator writes out the Euclidean algorithm line by line, and the quadratic solver walks from discriminant to simplified roots. The answer alone teaches nothing; the working is what you check homework against.

Do they work offline?

Yes — every computation runs in your browser with no server involved, so once a page has loaded it works with the connection off.