Generate a valid Chrome extension manifest.json in seconds. Pick permissions, content scripts, and pages — copy the result, drop it in your extension.
{
"manifest_version": 3,
"name": "My Awesome Extension",
"version": "1.0.0",
"description": "A Chrome extension built with PlugThis",
"permissions": [
"storage",
"activeTab"
],
"action": {
"default_popup": "popup.html"
},
"background": {
"service_worker": "background.js",
"type": "module"
}
}A working extension also needs the JS, HTML, and CSS that the manifest points to. PlugThis generates the whole bundle.
Build the full extension →Describe what you want in plain English. PlugThis generates a working Manifest V3 Chrome extension in under two minutes.
Open the builderThe manifest.json file is the heart of every Chrome extension. It tells Chrome the extension's name, version, what permissions it needs, which files run as content scripts, and what UI elements (popup, options page, icons) it provides.
Without a valid manifest, Chrome will not load the extension. Manifest V3 is the current standard — Chrome stopped accepting Manifest V2 extensions in the Web Store in 2024.
This tool produces a syntactically correct Manifest V3 file based on the options you select. It handles the formatting, structure, and required fields — you don't need to remember the exact JSON syntax.
The output is the same format Chrome expects: drop the generated content into a file named manifest.json at the root of your extension folder, and Chrome will recognize it on load.
The manifest is one file. A working Chrome extension is usually 5–15 files including content scripts, popup HTML, popup JavaScript, background workers, icons, and stylesheets — plus the wiring between them.
This tool produces the manifest. To produce the full extension, you can either write the rest of the code yourself, or describe what you want in plain English and let PlugThis generate everything (manifest plus all the supporting code) in under five minutes.
Yes. The output conforms to the Chrome Manifest V3 schema. You can drop it directly into an extension folder and Chrome will load it.
Just the ones you'll use. Asking for permissions you don't need triggers a more aggressive Chrome Web Store review and discourages users from installing.
More answers below.
Edge yes — it uses the same Manifest V3 format as Chrome. Firefox supports Manifest V3 with some differences; most fields work, but a few advanced features differ. The generator output is Chrome-first.
More answers below.
activeTab grants access to the current tab only when the user clicks the extension. tabs grants access to all tabs all the time. Use activeTab whenever possible — it requires no permission warning.
More answers below.
Yes. Click the Embed button on the generator to get an iframe code snippet you can paste into any site.
More answers below.
Pick a Chrome extension permission and see exactly what it allows, the risk level, and less invasive alternatives. Or paste a manifest to audit it.
Describe a workflow you want to improve. Get 3 tailored Chrome extension ideas you can build in under 10 minutes.