Calculators
Percentages, loans, dates, mortgages and statistics, with the formula always shown. All 30 of them run in your browser — nothing is uploaded.
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Every percentage question in one place.
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Exact age in years, months and days.
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Monthly payment, total interest and full amortisation.
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The real monthly cost, not just principal and interest.
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Growth over time, with regular contributions.
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Final price, amount saved, and stacked discounts.
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Tip, total, and the split per person.
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How long between two dates, in every unit.
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Add and subtract hours, minutes and seconds.
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Weighted GPA, semester averages and what you need on the final.
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A real expression calculator with a safe parser.
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Convert between hourly, daily, weekly, monthly and yearly pay.
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A live countdown to any date.
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Add, subtract, multiply and divide fractions — with the steps.
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Mean, median, mode, range and sum from a list of numbers.
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Variance, standard deviation and the rest of the summary.
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Add tax, remove tax, or find the rate.
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Roots, discriminant, vertex and the worked steps.
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Return on investment, margin, markup and payback.
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Pace, time and distance for runners.
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Work out what to save each month to hit a target.
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Compare avalanche and snowball across all your debts.
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Project a pension pot and the income it pays.
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Cost a journey in litres per 100 km or mpg.
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See what an appliance costs to run.
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Split a bill evenly or by what each person had.
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How much paint a room needs, and how many tins.
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Tiles, boxes and wastage for a floor or a wall.
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What you need on the final, and what it gets you.
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The right screen for your sofa, and the width it needs.
Other categories
- PDF Tools — Merge, split, compress, sign and convert PDF files without uploading a single page.
- Image Tools — Compress, resize, crop and convert photos with Canvas — the fastest tools on the site.
- Health & Body — Body measures, energy needs, cycles and sleep — every formula named, and none of it sent anywhere.
- Converters — Units, temperature, time zones, data sizes and number systems.
- Text Tools — Count, compare, clean, transform and read text aloud.
- Developer Tools — JSON, Base64, hashes, regex, JWT and the rest of the daily toolkit.
- Design & Color — Colour conversion, palettes, gradients, shadows and accessibility checks.
- Generators & Security — QR codes, passwords, UUIDs, signatures, invoices and random pickers.
- Utilities & Media — Timers, recorders, device tests and archive tools that use your hardware directly.
- Office & Productivity — Spreadsheets, CSVs, timesheets, labels and the small jobs that eat an office afternoon.