Calculators

Free online calculators for percentage, discount, sales tax and VAT

Fast, accurate calculators for the everyday math you can't be bothered to do in your head. Percentage, discount, sales tax and VAT — all free, all mobile-friendly, no ads getting in the way.

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Every Calculators tool you'll need

Hand-picked, free and unlimited. Click any tool to open it.

Percentage Calculator

Calculate percentages, percent increase, decrease and change.

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Discount Calculator

Find the sale price and total savings on any discount.

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Sales Tax Calculator

Add sales tax to any pre-tax price instantly.

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VAT Calculator

Add or remove VAT at any rate — UK, EU and worldwide.

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Why use these tools

What makes our Calculators tools different

Instant, accurate results

Every calculator updates as you type. No 'Calculate' button, no page reload, no waiting.

Step-by-step formulas shown

Each tool shows the formula it used so you can learn the math, not just the answer.

Mobile-first design

Number pads, large tap targets and zero clutter — built for phone use first.

Works offline once loaded

The calculators run entirely in your browser. No server round-trip, no tracking.

In depth

The complete guide to calculators

Specialised calculators are faster and less error-prone than a generic calculator app — they label the inputs, show the formula and handle edge cases you'd otherwise get wrong (like net vs. gross VAT). Our calculator suite covers the four most common money-math operations everyone does almost daily.

Percentage calculator — more than just %

Beyond 'what is 15% of 240', the percentage calculator handles percent increase ('I went from 80kg to 92kg, what's the gain?'), percent decrease, and percent of percent. Each operation has its own labelled input pair, so there's no guessing which number goes where.

Discount calculator

Stack a percentage discount on top of a fixed-amount voucher, see the final sale price and the total amount saved. Useful for shoppers, ecommerce operators reviewing promo strategies, and anyone trying to figure out whether a 'buy one get one 40% off' deal beats a flat 25% off.

Sales tax and VAT

US-style sales tax is added to a pre-tax price; EU/UK VAT is usually shown gross and removed to find the net. The two calculators handle both directions so you don't have to guess whether you should multiply or divide by 1.20.

Designed for daily, repeated use

Everything updates as you type, the formula is always visible, and the URL is short and memorable so you can bookmark it. No ads block the answer, no popup asks for your email — just the number you came for.

FAQ

Frequently asked questions

Are these calculators free?+

Yes — every calculator is 100% free with no usage limits and no signup.

Do they work on mobile?+

Yes. Each calculator is built mobile-first with large tap targets and number-pad inputs.

Are the results accurate?+

Yes. All math runs locally in your browser using standard floating-point arithmetic and is verified against known formulas.

Can I see the formula?+

Yes — every calculator displays the formula and a step-by-step breakdown alongside the result.

Is my input data stored?+

No. All calculations happen in your browser. Nothing is sent to our servers and nothing is logged.

Which VAT rates are supported?+

Any rate. Type the percentage that applies to your country or transaction — UK 20%, Ireland 23%, Germany 19%, or any custom rate.

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