Makefile Linter
Makefile Linter
Lint a GNU Makefile for the classic tab-vs-spaces "missing separator" mistake, duplicate target definitions, undefined variables and target references, and phony-looking targets missing from .PHONY; or generate a starter Makefile from a Node.js/Go/Generic preset with editable variables, .PHONY targets, and target dependencies — entirely client-side.
Paste a Makefile above to check for the tab-vs-spaces "missing separator" mistake, duplicate targets, undefined variables and targets, and missing .PHONY declarations.
Client-side heuristic linter for GNU Makefiles — checks recipe-line tab/space separators, duplicate target definitions, targets/variables referenced but never defined, and phony-looking targets missing from .PHONY. It parses line-by-line rather than running a real Make preprocessor, so "undefined target" findings are informational — they may simply be real files that exist on disk.
Makefile Linter
Lint a GNU Makefile for the classic tab-vs-spaces "missing separator" mistake, duplicate target definitions, undefined variables and target references, and phony-looking targets missing from .PHONY; or generate a starter Makefile from a Node.js/Go/Generic preset with editable variables, .PHONY targets, and target dependencies — entirely client-side.
Common uses
- Find the missing tab causing "*** missing separator"
- Check for targets missing from .PHONY
- Spot a duplicate target definition
- Generate a starter Makefile for a Node.js project
- Generate a Makefile with build/test/clean targets and dependencies
Also searched as
- makefile linter online
- makefile missing separator fix
- makefile tabs vs spaces error
- makefile syntax checker
- makefile phony targets check
- makefile duplicate target
- makefile undefined variable
- generate makefile for node project
- makefile template for go
- starter makefile build test clean
Frequently asked questions
Why do I get '*** missing separator' in my Makefile?
It usually means a recipe line starts with spaces instead of a tab. The linter flags those lines.
What else does the linter check?
Duplicate targets, undefined variables and target references, and phony-looking targets missing from .PHONY.
Can it generate a Makefile?
Yes, the Generate tab builds a starter Makefile from a Node.js, Go or Generic preset with editable variables and dependencies.
Does it run make?
No, it lints the pasted text only, in your browser.
Is my data uploaded to a server?
No. This tool runs entirely in your browser — your input is processed locally on your device and is never uploaded or stored on a server.