Git & Version Control
Check one literal branch, reference or object ID. Keep syntax errors separate from naming advice.
Enter a name or hash to begin.
Text is checked in this browser; no repository access or input upload occurs.
One value, up to 4,096 UTF-16 code units. Diagnostics are shown 50 at a time.
Enter a name or hash to begin.
Git branch name validator helps when a branch command rejects a name that looks ordinary. A pasted space, a dot at a path boundary or a reserved suffix may be hard to spot in a terminal message.
Start by choosing what the text represents. The same main string passes as a branch but needs the single-level option as a reference. A hexadecimal string needs an algorithm context before its length can be interpreted.
The Git branch name validator reports individual positions while preserving every input character. An optional ASCII candidate appears separately, so a syntactic diagnosis does not quietly rename your branch or erase a meaningful character.
A long object ID can be shortened for a release note, but that prefix might match several objects. The hash report identifies full versus abbreviated format and displays only existing characters; it never invents the missing suffix.
Switching modes keeps the same input. For a full branch reference enter refs/heads/main; for a branch shorthand enter main. The single-level checkbox only removes the reference mode’s slash requirement.
Choose SHA-1 for a 40-character full ID or SHA-256 for a 64-character full ID. When abbreviations are enabled, 4 characters through one less than the full length are accepted as abbreviated format.
Automatic checking waits 350 ms after edits. Turn it off for a manual run or press Ctrl/Cmd + Enter. Clicking a diagnostic moves the editor to its line and column.
Git branch naming rules add branch-specific restrictions such as HEAD and a leading hyphen. Reference checks can allow one-level names explicitly. Rules follow literal git check-ref-format semantics, without expanding checkout history.
The report finds forbidden ASCII controls, spaces, punctuation and sequences such as .. and @{. Slash-separated components cannot start with a dot or end in .lock. Positions use one-based lines and UTF-16 columns; JSON also carries exact offsets.
The generator lowercases ASCII and replaces characters outside letters, digits, dot, underscore, slash and hyphen. It repairs forbidden structures and checks the candidate again. Non-Latin text is not transliterated; an empty usable name becomes branch.
A short Git hash is assessed against the selected algorithm. Forty hexadecimal characters are a full SHA-1 ID but an abbreviated SHA-256 ID. Uppercase hex remains uppercase, and the exported report records the algorithm and whether an abbreviation was accepted.
Use branch mode for a literal name, or run git check-ref-format --branch with the name as a quoted argument in your own shell. A valid report checks spelling rules only. main and master are not forbidden names merely because a team may protect them.
Git rejects ASCII control characters, spaces, ~, ^, :, ?, *, [, and backslash, as well as forbidden sequences and component boundaries. A closing ] or a dollar sign is not a Git syntax error, although shell quoting may be required. Branch HEAD is separately reserved.
The default command validates a reference name and expects a slash. Branch mode checks the shorthand in the branch namespace instead. Use the appropriate context; do not append a meaningless slash, because trailing slashes are also invalid.
Git chooses a repository-unique prefix, with a minimum requested length of four; the default comes from core.abbrev. Seven is only this page’s display default. Copying the first seven characters cannot prove that no other object shares them.
You must query that repository. For example, git cat-file -e with an appropriate object expression can check existence, and a commit-type check is a separate concern. A full hexadecimal ID, even one with the expected length, does not prove an object or commit exists.
Still have a question?
Use the Git branch name validator to explain the syntax first, then verify repository-dependent facts where the branch or object will be used.