formik
Build forms in React, without the tears
About
Build forms in React, without the tears
What detecting formik tells you about a site
formik reveals controlled, state-driven form handling — the established alternative to react-hook-form. Finding it (especially over react-hook-form) often marks an older React codebase or a team standardised on Formik's render-prop/component model for complex multi-step forms.
Why the exact formik version matters
Formik's API has been stable across 2.x but the library is far less actively maintained than react-hook-form; the exact version, and whether it is current, is a useful read on the codebase's age and upgrade appetite.
formik in a real-world stack
When you find formik in a bundle, it rarely travels alone. yup for schema validation (the classic Formik pairing), and a UI component library for the inputs.
Quick facts
npm install formikCommon pairings
Packages this one expects to find in the same project. Each is also a Sourcemap Explorer detection target.
What formik pulls in
formik declares 8 direct dependencies — each one also rides into any bundle that ships formik, so they are detection targets too. Reading them is a quick way to understand the package's real footprint .
How Sourcemap Explorer detects formik
formik ships as v2.4.9, published 2025-11-10 and carries 8 direct dependencies, 1 peer dependency (react), 214 versions on the registry. Those exact numbers are the footprint Sourcemap Explorer matches when formik rides inside a deployed bundle — here is how the detection works.
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 — that map is where the `formik` paths live.
- 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.
Major releases of formik
When each major version first landed. Major bumps are where breaking changes live, so this timeline is the fastest way to date the formik version a site actually ships against the ecosystem.
Recent versions
formik README
Live mirror of the GitHub README, for reference. 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)
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.
How do I find out which version of formik a website is running?
Read it straight from the site's JavaScript sourcemap. When a build ships source maps, the bundled `formik/package.json` carries the exact `version` string — Sourcemap Explorer extracts it in one click on the Stack tab, and you can do it by hand in DevTools by opening the `.map` file and searching for `node_modules/formik/package.json`. That is far more reliable than inferring the version from an asset-hash or a `?ver=` query string, which is all surface-level detectors have to go on. The current npm release is 2.4.9, but real deployments frequently run an older pinned version — which is exactly why reading the bundled number matters.
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.
Is formik actively maintained?
Actively maintained — the package is shipping new releases at a steady cadence. The last published release was 2025-11-10. Source code: https://github.com/jaredpalmer/formik.
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 (the registry's latest is v2.4.9, published 2025-11-10; the bundled copy is often older). Without sourcemaps, an import / require in the page's scripts is enough to flag it.