ToolBook
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Our story

The toolbox we wished existed.

Most online tools look like they were built in 2003. Numbers in plain boxes. Pop-ups stacked five deep. Ads where the answer should be. We thought you deserved better, so we built it.

Tools live

54

Categories

5

What we believe.

  • Free, forever

    Every tool here is free, will stay free, and never sits behind a signup form. The interface and the math are the product — not the data we collect.

  • Visual results, not just numbers

    A number in a box is not an answer. A chart is. An animation is. A coloured breakdown is. Every result on ToolBook tries to show you what it actually means.

  • Fast, in your browser

    No server round-trips for math. No API keys to manage. Open the tool, type, see the answer. Works offline once the page is loaded.

  • Accurate, by design

    Every tool runs the actual textbook formula, not a hand-wavy approximation. Inputs are validated, edge cases are handled, and the math is verifiable.

What we don't.

For every yes, a no. These are the patterns you'll never see on ToolBook — not because we're too good for them, because they're bad for you.

  • Pop-ups asking for your email
  • Five ad slots above the fold
  • Cookie banners when there are no cookies
  • "Sign up for premium" walls on basic features
  • Dark patterns that hide the tool you came for
  • Newsletter overlays after 10 seconds

Where we're going.

54 tools live and growing. We ship new ones regularly — image utilities, PDF tools, more developer tooling, and plain-English explainers for every calculator. If there's a tool you wish existed, the fastest way to get it built is to tell us.

Built for builders

Free, forever — and made for the way you actually work.