# Free tools

Canonical: https://www.formlightoptics.com/tools
Markdown: https://www.formlightoptics.com/tools.md

Two calculators for first-order illumination checks. They run in the browser. Nothing is uploaded and nothing is stored.

- [LED beam angle calculator](https://www.formlightoptics.com/tools/led-beam-angle): Full beam angle from a spot diameter and throw, or the reverse, plus optional on-axis illuminance.
- [Etendue calculator](https://www.formlightoptics.com/tools/etendue): Source etendue against a fiber or an aperture, and the geometric coupling ceiling.

Need more than an estimate? Get a fixed-fee design quote.

https://www.formlightoptics.com/contact