Format and lint your code directly inside automation platform editors No copy-paste to VS Code or any other editor required. Supported Platforms

Zapier (Code by Zapier action: JavaScript and Python)
n8n (Code nodes: JavaScript and Python, on n8n.io and n8n.cloud)
Pipedream (Code steps: JavaScript and Python)
Make (JavaScript code modules)
HubSpot Data Hub (custom code actions: JavaScript and Python)
HubSpot CMS / Design Manager (HubL templates with HTML and CSS contexts, plus module.js)

How It Works

Open a code editor on any supported platform.
Use any of three ways to format:
Click the codefmt icon in your browser toolbar, then press Format Code. Lint diagnostics are listed directly in the popup.
Right-click and select Format with codefmt (format only) or Fix with codefmt (format + safe lint fixes + organize imports).
Press the keyboard shortcut:
- Mac: Cmd+Shift+F
- Windows/Linux: Ctrl+Shift+F
Your code is formatted and written back to the editor instantly.
A notification appears in the editor confirming the format and the number of lint diagnostics found.

Features

Platform-aware formatting that understands each platform's code structure:
Async wrappers
Globals
Return styles
Line-width conventions
Auto-detects:
JavaScript
Python
HubL (including HTML, CSS, and JavaScript contexts inside HubSpot Design Manager)
Instant lint diagnostics powered by:
oxlint for JavaScript (benchmarked by the Oxc project at 50–100× faster than ESLint)
Ruff for Python
JavaScript and TypeScript formatting powered by Biome, with Prettier-compatible output
Python formatting and linting powered by Ruff
HubL formatting and linting via a custom formatter built for HubSpot CMS templates
Fix with codefmt right-click action that applies safe Biome lint fixes and organize imports in one pass
Configurable formatting options:
Print width
Quote style
Semicolons
Trailing commas
Bracket spacing
Arrow parens
JSX quote style
Quote properties
Bracket same line
Organize imports
Sync settings from codefmt.dev with one click:
Configure on the web
Use in the extension
Settings are stored per platform
Customizable keyboard shortcut:
Default: Cmd+Shift+F / Ctrl+Shift+F
Remap at chrome://extensions/shortcuts
Light and dark theme support, following your system by default
Per-tab badge displays fmt on supported sites so you know the extension is active
Works with:
Monaco Editor
CodeMirror 5
CodeMirror 6
50 KB code size limit per format request
30-second request timeout with automatic retry on transient network failures

Privacy and Data Handling

No accounts
No cookies
No tracking
No telemetry
Formatting preferences are stored locally in your browser only
When you trigger a format:
The code currently in your editor is sent over HTTPS to codefmt.dev/api/format
Processed in memory
Returned formatted
Processing uses short-lived in-memory buffers and ephemeral temporary files
Temporary files are deleted immediately after the response is sent
Nothing is persisted to any database, logged, or shared with third parties
The extension only runs on:
Supported platform domains listed above
codefmt.dev (for the optional settings sync feature)

Security

Built On Biome: Rust-based, Prettier-compatible formatter that powers JavaScript and TypeScript output.

oxlint: Rust-based JavaScript linter with a familiar rule set.

Ruff: Rust-based Python formatter and linter used by major Python projects.

Learn More Web Formatter

About and Support

codefmt

Published Firefox add-on: