Icon Licensing: What to Know Before You Ship
By Nomadic Jeikei · Updated July 24, 2026
Because open-source icons are 'free,' it's easy to assume you can use them with no strings attached. In reality, each license has different attribution obligations, and CC BY in particular requires visible credit inside your app. This guide covers the four licenses you'll meet most often and how to use them cleanly in a commercial product.
The four licenses you'll meet most
The license on an icon set is almost always one of four. All four permit commercial use — what differs is where and how much you have to attribute.
| License | Commercial use | Attribution |
|---|---|---|
| MIT | Yes | Keep the copyright notice in source (no UI credit) |
| ISC | Yes | Same as MIT, just shorter wording |
| Apache 2.0 | Yes | Copyright + license copy; include NOTICE if present |
| CC BY 4.0 | Yes | Visible credit to the author, with a link |
The key split: MIT, ISC, and Apache let you keep the notice 'inside your source or distribution,' while CC BY 4.0 requires a credit 'somewhere the user can see it.' If you can't add attribution to a settings or about screen, it's safer to avoid CC BY icons.
What each license actually asks of you
MIT and ISC are the easiest to work with. Keep the original copyright notice somewhere in your project — a license file, an open-source notices screen — and you're done; you don't need to surface the author's name in the visible UI.
Apache 2.0 adds two things. You ship a copy of the full license text, and if the original includes a NOTICE file, you include its contents too. You'll see this most on code libraries, but it can apply to icon sets as well.
CC BY 4.0 carries the heaviest conditions. You must credit the author's name, link to the original, indicate the license, and note if you made changes — all in a form the user can see. For a website that's usually the footer; for an app, an 'open-source licenses' screen.
Where Lucide and Iconify fit
The two sources App Ready's ICONS draws from behave differently. Lucide is ISC-licensed across the whole set, so you can use it in a commercial app with no UI credit — just keep the license notice in your source. If you're new to icon licensing, Lucide is the safest starting point.
Iconify, by contrast, is a hub that aggregates hundreds of sets. Each set carries its own license, so being on Iconify doesn't mean the terms are the same. Fortunately many popular sets — Heroicons, Tabler, Phosphor, Bootstrap Icons — are MIT or ISC and easy to handle, but you should always check that specific set's license before using it.
- Check the license name shown on the set's page or description first
- MIT/ISC: keep the notice in source. Apache: check for a NOTICE file
- CC BY: confirm you have room for a visible credit in your app
- If unsure, swap in an MIT/ISC set such as Lucide
In short — three steps to stay safe
- 1. Check the set's license before you pick an icon
- 2. MIT/ISC: source notice. Apache: include NOTICE. CC BY: visible credit
- 3. Keep one 'open-source licenses' screen where all notices live
For most solo projects, MIT and ISC icons are all you need. Check the per-set license in ICONS, pick the icons you want, and download them as SVG or PNG — and your icon prep is done without licensing worries.
Frequently asked questions
- If an icon is 'free,' can I use it without attribution?
- It depends on the license. MIT and ISC only need a notice in your source — no UI credit — but CC BY 4.0 requires visible credit to the user. 'Free' and 'no conditions' are not the same thing.
- Can I use Lucide icons in a commercial app as-is?
- Yes. Lucide is ISC-licensed, which permits commercial use and requires no visible UI credit. As a matter of principle, keep the license notice somewhere in your project's source.
- Do all icons on Iconify share the same license?
- No. Iconify is a hub aggregating hundreds of sets with different licenses. Terms vary per set, so check each set's license individually before using it.