SPDX License Diff

Name: SPDX License Diff
Rating: 5 (1 reviews)
Author: Alan Tse

By: Alan Tse Add-on

Diff selected text against SPDX licenses

Overview

Firefox Add-ons Store

Daily users

17 ▲ 2

Data as of 2026-07-31

Rating:

5.00

(1)

Version:

0.13.1

Last updated: 2026-06-19

Features & Capabilities

This open source extension creates a browser button in Chrome to compare selected text against the SPDX License List (https://spdx.org/licenses/). It will then show the closest matching license and provide a redline showing differences against the canonical SPDX license text. This can be useful when trying to identify an open source license or determining if it has been changed.

The SPDX License List is a list of commonly found licenses and exceptions used in free and open source and other collaborative software or documentation. The purpose of the SPDX License List is to enable easy and efficient identification of such licenses and exceptions in an SPDX document, in source files or elsewhere. The SPDX License List includes a standardized short identifier, full name, vetted license text including matching guidelines markup as appropriate, and a canonical permanent URL for each license and exception.

Released under GPL-3.0 (for now)

User Growth & Download Statistics

Add-on

By:

Daily users:

Rating:

Version:

0.13.1 Last updated: 2026-06-19

Version code:

6314943

Creation date:

2019-07-05

Risk:

Permissions:

Host permissions:

*://*.spdx.org/*

Size:

180.21KB

URLs:

Website

Full description:

Source:

Firefox Add-ons Store

Data ingested on:

2026-07-31

Compare stats and ranking:

Ranking

# 25,343 ▲ 1,321

Other rankings

#1 in license keyword 4

Other platforms

SPDX License Diff (v0.13.1)

186 5.00

(4)

For Developers

Monetize with App Pass Boost with Extension Booster

Contact the developer

Chrome-Stats does not own this Firefox add-on. Please use these information below to contact the Firefox add-on developer.

Developed by:

Alan Tse

Firefox Add-ons Store

https://addons.mozilla.org/firefox/addon/spdx-license-diff/

Website:

https://github.com/spdx/spdx-license-diff/issues

Permission Change History

2025-06-10: Version 0.9.2 → 0.10.0

Add Host permissions: *://*.spdx.org/*

Add Permissions: scripting

Remove Permissions: *://*.spdx.org/*

Is SPDX License Diff Safe?

Risk impact

Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypassing your security settings, and accessing your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.

SPDX License Diff requires very minimum permissions.

Risk impact analysis details

Low Request access to the following domains: spdx.org

Risk likelihood

Risk likelihood measures the probability that a Firefox add-on may turn malicious. This is determined by the publisher and the Firefox add-on reputation on Firefox Add-ons Store, the amount of time the Firefox add-on has been around, and other signals about the Firefox add-on. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Firefox add-on.

SPDX License Diff is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.

Risk likelihood analysis details

High This extension has low user count. Unpopular extensions may not be stable or safe.
Medium **** ********* *** ******* ** *** **** * ******* *** ******* *** *** ** ****** ** *****
Low **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****
Good **** ********* *** **** **** *******