Comparison

react-iframe-kit covers three jobs that usually take three packages. If you only need one of them and already use a good library for it, you may not need this one.

	react-iframe-kit	react-frame-component	iframe-resizer	Penpal	Comlink
Render React into an iframe	✅	✅	—	—	—
Mounts only into the final document	✅	⚠️ ¹	—	—	—
Resize, same-origin	✅	—	✅	—	—
Resize, cross-origin	✅	—	✅	—	—
Method calls	✅	—	⚠️ ²	✅	✅
Events	✅	—	⚠️ ²	—	—
Typed calls	✅	—	—	✅	✅
React hooks	✅	component	✅ ³	—	—
Host page without React	✅ ⁶	—	✅	✅	✅
Load and timeout status	✅	—	—	⚠️ ⁷	—
Runtime validation of arguments	✅ ⁸	—	—	—	—
Origin checks enforced	✅	n/a	configurable	configurable	optional ⁴
One connection for everything	✅	n/a	n/a	n/a	n/a
Built for	iframes	iframes	iframes	iframes, workers, windows	workers ⁵
License	MIT	MIT	GPL-3.0 or commercial (v5+) ⁹	MIT	Apache-2.0

Notes:

1. It portals into the iframe’s current document, which may still be the temporary one, depending on the browser and on whether you pass initialContent (a srcdoc); see Portal rendering.
2. Untyped messages between the two sides, not request/response calls.
3. Through a separate React package.
4. Its window endpoint can be limited to an origin, but nothing makes you.
5. Iframes through a window adapter.
6. react-iframe-kit/host, also as a <script> build (next release).
7. The connection promise rejects after a timeout; there is no load state for an iframe that doesn’t run the library.
8. react-iframe-kit/validate, with any Standard Schema library (next release).
9. Cross-origin use needs a paid license from v5. 4.x and iframe-resizer-react 1.x are MIT but no longer updated.

Note

This table reflects each project’s documented features as of September 2026, written by the author of react-iframe-kit. Check the other projects’ docs, and their licenses, before deciding. Corrections are welcome as issues.

When to pick something else

• Only RPC to a web worker: Comlink. react-iframe-kit is iframe-only by design.
• Deeply nested objects or callbacks across the boundary: Comlink’s proxies do that. Here, remote is a flat method map and only cloneable data crosses.
• You already run iframe-resizer and only need resizing: it’s mature and widely used. The two use different wire protocols and can’t talk to each other. If its license is why you’re looking, see Migrate from iframe-resizer.