International Day of Light 2025

International Day of Light celebrates light science and its applications in culture, education and sustainable development.

Frequently asked questions

When is International Day of Light 2025?

International Day of Light 2025 is on Friday, 16 May 2025.

What day of the week is International Day of Light 2025?

It falls on Friday.

How is International Day of Light calculated?

This event is observed every year on 16 May.