MathFill: Equation Editor for Slides™ & Docs™ — Terms of Service
Last updated: 26 October 2026
These terms are between you and Spyridon Pikoulas, who makes MathFill, an add-on for Google Slides™ and Google Docs™. Installing or using MathFill means you accept them.
The service
MathFill lets you write equations, choose their size and color, insert them as images into the presentation or document you open it in, and edit equations it inserted. It is built on open-source software and fonts, MathLive (MIT License) and MathJax (Apache License 2.0) with the MathJax TeX fonts (SIL Open Font License 1.1), whose licenses are in the add-on and at pikoulas.com/mathfill/licenses.
Free use and the one-time purchase
Each Google account gets 10 equations or edits free in total. One is one new equation image placed in your file, or one equation MathFill inserted that is updated after an edit; previewing, and inserts or edits that MathFill refuses before placing, use none. A request with an uncertain outcome keeps its reserved use unavailable; it is not automatically refunded or repeated. If that happens, write to us and we will restore it.
After that, MathFill is a $9 one-time unlock per Google account for unlimited equations and edits, paid through Stripe at the price shown before you pay, plus any tax due. There is no subscription or automatic renewal. Google’s service limits apply to free and paid use.
Any payment can be refunded within 14 days: write to the address below with the Google account email used for the purchase. A full refund or dispute removes the unlock when a later billing check finds it; checks are normally cached for six hours, so this is not instant.
Your part
Use MathFill lawfully and within Google’s terms. Don’t try to get around the free limit or the purchase check. Check the equations you insert: MathFill draws what you write.
Warranty and liability
MathFill is provided as it is, without warranty of any kind. To the extent the law allows, we are not liable for indirect or consequential loss, and our total liability is limited to what you paid for MathFill in the 12 months before the claim. Nothing here limits rights you have as a consumer that cannot be limited.
Changes
We may change these terms or MathFill’s price. A new price applies to future purchases. The date at the top shows the latest version. Danish law governs these terms.