About Toolstack

Toolstack is a growing collection of free, single-purpose online tools — built to do one job well, load fast, and work without asking you to sign up, install anything, or hand over your data.

We started with practical, everyday utilities for developers and everyday users: merging JSON files, converting formats, and more tools on the way, including calculators for logistics, shipping, and general-purpose use.

What we believe in

No sign-up required. Every tool works the moment you open it.
Privacy by design. Where possible, our tools process your data directly in your browser — nothing is uploaded to a server or stored by us.
Fast and simple. No clutter, no unnecessary steps — just the tool you came for.
Always free to use. Core tools remain free; the site is supported through advertising and optional upgrades.

Toolstack is actively growing — new tools are added regularly based on what people are actually searching for and struggling to find good free options for. If there's a tool you wish existed, we'd love to hear about it on our Contact page.