formik
Build forms in React, without the tears
About
Build forms in React, without the tears
Live mirror of the GitHub README. Updated whenever the repo's default branch changes.
Build forms in React, without the tears.
Visit https://formik.org to get started with Formik.
Organizations and projects using Formik
List of organizations and projects using Formik
Authors
- Jared Palmer @jaredpalmer
- Ian White @eonwhite
Contributing
This monorepo uses yarn, so to start you'll need the package manager installed.
To run E2E tests you'll also need Playwright set up, which can be done locally via npx playwright install. Afterward, run yarn start:app and in a separate tab run yarn e2e:ui to boot up the test runner.
When you're done with your changes, we use changesets to manage release notes. Run yarn changeset to autogenerate notes to be appended to your pull request.
Thank you!
Contributors
Formik is made with <3 thanks to these wonderful people (emoji key):
 Jared Palmer 💬 💻 🎨 📖 💡 🤔 👀 ⚠️ |  Ian White 💬 🐛 💻 📖 🤔 👀 |  Andrej Badin 💬 🐛 📖 |  Adam Howard 💬 🐛 🤔 👀 |  Vlad Shcherbin 💬 🐛 🤔 |  Brikou CARRE 🐛 📖 |  Sam Kvale 🐛 💻 ⚠️ |
|---|---|---|---|---|---|---|
 Jon Tansey 🐛 💻 |  Tyler Martinez 🐛 📖 |  Tobias Lohse 🐛 💻 |
This project follows the all-contributors specification. Contributions of any kind welcome!
Related
- TSDX - Zero-config CLI for TypeScript used by this repo. (Formik's Rollup configuration as a CLI)
Quick facts
npm install formikCommon pairings
Packages this one expects to find in the same project. Each is also a Sourcemap Explorer detection target.
How Sourcemap Explorer detects formik
We catch formik from two complementary signals: bundled source paths and the embedded package.json. Modern bundlers (webpack, Vite, esbuild, Rollup, Turbopack) preserve the original node_modules/formik/ paths inside the JavaScript sourcemap's sources[] array — that's the canonical signal. When the matching package.json is also captured in sourcesContent[], we read the exact version field — patch number included. No regex guessing, no version inference.
- 1
Confirm the site exposes sourcemaps
In DevTools Network, check the response headers of any application script for `SourceMap` or `X-SourceMap`. Failing that, fetch the script's last 4 KB and look for a `//# sourceMappingURL=` comment.
- 2
Find the package in the bundle
Open DevTools → Network → reload. Click any application script and look at its sourcemap. Inside, search `sources[]` for entries matching `node_modules/formik/` — every match confirms the package is bundled. The matching `sourcesContent[i]` for `node_modules/formik/package.json` gives you the exact installed version.
- 3
Read the version directly from package.json
Run `jq -r '. as $m | $m.sources | to_entries[] | select(.value | endswith("node_modules/formik/package.json")) | $m.sourcesContent[.key] | fromjson | .version' bundle.js.map`. Sourcemap Explorer automates the same query in the popup.
Recent versions
FAQ
What is formik used for?
Build forms in React, without the tears
How can I tell if a website is using formik?
Open the page in Chrome with the Sourcemap Explorer extension installed and read the Stack tab. We catch `formik` from two complementary signals: `node_modules/formik/` paths inside the JavaScript sourcemap, and the embedded `package.json` we read for exact-version detection. Without the extension you can do the same lookup manually in DevTools — the steps are listed in the "How Sourcemap Explorer detects" section above.
What is the latest version of formik?
2.4.9, as published on the npm registry. The "Recent versions" table on this page lists the most recent 8 releases with their release dates. Sourcemap Explorer reports the version actually bundled into a site, which can lag the latest release by months on real-world deployments.
Where can I read more?
Project homepage: https://formik.org. Source code: https://github.com/jaredpalmer/formik. Published on npm: https://www.npmjs.com/package/formik. Licensed as Apache-2.0.
Keep reading on Sourcemap Explorer
Detected by Sourcemap Explorer
When a bundle ships sourcemaps, we read the embedded package.json for formik and report the precise version. Without sourcemaps, an import / require in the page's scripts is enough to flag it.