About iToolsLab

iToolsLab is a growing library of free online tools that are fast, private and explained in plain language.

Why we built it

iToolsLab started from a simple frustration: many online tools are slow, crowded with pop ups, ask you to sign up or upload private files for a task that takes one line of code. We wanted tools that load quickly, respect your privacy and show their working.

Every tool on iToolsLab runs in your browser. Your text, numbers and images stay on your device. There is nothing to install and nothing to sign up for.

How we make and check tools

Each tool begins with a published formula or a clear standard, such as the WHO ranges for body mass index or the Web Crypto API for random numbers. We test with worked examples and edge cases, and we show the formula and an example on the page so you can verify the result yourself.

When a standard changes, or a reader finds a mistake, we correct the tool and update the date shown on the page.

How we are funded

iToolsLab is free to use and is supported by advertising. Ads never change a calculation or a result. We do not sell your data because we do not collect the content you enter into our tools.

Contact

Questions, corrections and tool requests are welcome. Please use the contact page.