License Generator
Pick a licence and generate the LICENSE file text with your year and copyright holder.
What is License?
A licence picker and generator. It writes the exact text for licences short enough to reproduce verbatim, and for the clause-numbered ones it writes the official file header with the canonical URL rather than a paraphrase.
How it works
Choose a licence and fill in the year and copyright holder. Permissive licences are emitted in full with the placeholders replaced; long copyleft licences return the standard file header, the SPDX identifier for package.json, and the URL of the authoritative text. Each licence also shows its permissions, conditions and limitations, so the choice can be made on the facts rather than on a summary.
- Paste or fill in the input. Drop in a commit message, a diff, a package.json, a path list or a set of options. The tool reads it locally — nothing is uploaded and no repository is contacted.
- Adjust the rules to match your project. Every linter here takes its convention from a setting you can change: allowed commit types, header length, target branch length, known branch names. Set them once to what your team actually uses.
- Copy the result. Generated files copy straight to the clipboard or download as a real file with the right name (.gitignore, CODEOWNERS, LICENSE, COMMIT_EDITMSG), and Reset returns every field to its default.
Examples
A commit message that fails CI
"Updated(auth): Fixed the expired-token redirect." is rejected by release automation and reported here with the exact reasons: unknown type, capitalised description, past tense and a trailing period.
A .gitignore that only half works
The Checker shows which rule decides a path — and why `!keep.txt` inside an ignored directory never fires, the mistake that sends people to Stack Overflow.
A dependency bump nobody reviewed
The package.json Diff separates added, removed and changed entries per section, so a caret bump of a runtime dependency does not hide inside a lockfile-sized pull request.
A diff pasted from a code review comment
The Diff Viewer understands several `diff --git` blocks, mode-only changes, renames and binary stubs, and calls out a pasted `--stat` summary instead of rendering an empty box.
Common mistakes
Committing a .gitignore without checking it
Rules look right and behave differently: a pattern containing a slash is anchored to the root, a trailing slash means directories only, and a file inside an ignored directory cannot be re-included. Check the paths that matter before you commit the file.
Rewriting published history
A clean commit history is worth having, but amend, rebase and filter-repo change commit hashes. Only rewrite commits that nobody has pulled; after a rewrite, push with --force-with-lease rather than --force.
Treating a generated file as if it were reviewed
These tools produce a starting point, not a decision. Check the licence text against the canonical source, read the security policy before publishing it, and make sure a CODEOWNERS team actually exists — GitHub silently ignores rules whose owner has no write access.
Putting slow checks in a pre-commit hook
A hook that takes 30 seconds gets bypassed with --no-verify within a week, and then it protects nothing. Keep pre-commit to formatting and linting, move type checks and tests to pre-push or CI.
Frequently asked questions
Why do some licences not include the full text?
Because reproducing a 35 kB legal document from memory risks a subtle, load-bearing error. For those licences the tool writes the header you paste into each source file, the SPDX identifier, and the URL of the canonical text — which is the part that has to be exact.
Do I need a licence at all?
If you want anyone to be able to use your code, yes. Without one, the default under copyright is that nobody may copy, modify or distribute it, even if the repository is public.
What should go in package.json?
The SPDX identifier from the table — `"license": "MIT"` rather than `"MIT License"` — so tools can read it. Use `UNLICENSED` with `"private": true` for something that is not meant to be published.