Freedom251 › File Comparison Software
Mergely
What Mergely is
Mergely is a browser-based editor and JavaScript library for comparing and merging two text documents. It displays the documents side by side and marks added, deleted and changed text. The comparison runs in the browser using JavaScript, without server calls for the diff. The maker says imported documents stay in the browser unless you save or share them; saved diffs are public to anyone with the link, who can view and manage the share. The open-source version is free under GPL, LGPL and MPL licenses. Developers can embed the library in a web application and use its API. Documentation recommends the React component and describes CDN and webpack use; the Angular component is out of date. Options include ignoring whitespace, case or accented characters, and displaying line numbers, wrapping and sidebars. The API can merge a whole document or a current change from one side to the other. Mergely lists Firefox, Chrome, Edge and Safari as supported browsers. Three-way merge and built-in syntax highlighting are not included; language modes can be added when compiling a custom version.
Who it suits
Mergely suits people comparing or merging two text documents in a browser, and developers embedding diff and merge capabilities in a web application. Its open-source licenses may suit projects able to use GPL, LGPL or MPL software.
What it does well
- Compares documents in the browser without server calls
- Marks added, deleted and changed text
- Can ignore whitespace, case or accented characters
- Offers an API for embedding and merge controls
- Free under GPL, LGPL and MPL licenses
What to know first
- Saved diffs are public to anyone with the link
- Does not support three-way merge
- Built-in syntax highlighting is unavailable
- Angular component is out of date
Limits
The free open-source version is distributed under GPL, LGPL, and MPL licenses. It supports two-way rather than three-way merge and does not provide built-in syntax highlighting.
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| Open-source license | GPL · LGPL · MPL | Free |
| Closed Distribution License (CDL) | Lifetime license for prior releases and releases in the following year · 1 year of personal email support | On request |
As mergely.com lists them, read 8 Oct 2026. The maker's own page has the final word.
Getting started
- Visit the Mergely website.
- Use the browser-based editor or embed the JavaScript library in a web application.
- For integration, follow the documented React, CDN, or webpack route.
- Choose an open-source license: GPL, LGPL, or MPL.
- Contact the maker about a Closed Distribution License if needed.
Verdict
Mergely provides browser-based two-document comparison and merge controls, with an API for web application integration. Consider its two-way scope, public link sharing and lack of built-in syntax highlighting when deciding whether it fits.
Questions
Is Mergely free?
Yes. The open-source plan costs nothing and is available under GPL, LGPL, and MPL licenses.
Which browsers does Mergely support?
The maker lists Firefox, Chrome, Edge, and Safari as supported HTML5-compatible browsers.
Are comparisons sent to a server?
The diff is computed in the browser without server calls. The maker says imported documents stay in the browser unless saved or shared.
Who can see a saved diff?
Saved diffs are public to anyone with the link, who can view and manage the share.
Does Mergely support three-way merge or syntax highlighting?
No. Three-way merge and built-in syntax highlighting are not supported.
Is there a commercial license?
A Closed Distribution License is available by contacting the maker. It includes a lifetime license for prior releases and releases in the following year, plus one year of personal email support.
Facts from Mergely's own pages
- Browser processing
- Mergely computes differences in the browser using JavaScript, without server calls for the comparison. · mergely.com, 8 Oct 2026
- Comparison
- It shows two documents side by side and highlights added, deleted, and changed text. · mergely.com, 8 Oct 2026
- Diff features
- Options include ignoring whitespace, case, or accented characters, line numbers, line wrapping, and sidebars. · mergely.com, 8 Oct 2026
- Embedding
- The library can be embedded in a web application and provides an API for integration. · mergely.com, 8 Oct 2026
- File privacy
- The maker says imported documents stay in the browser unless the user saves or shares them. · mergely.com, 8 Oct 2026
- Integrations
- The documentation recommends the React component and also describes CDN and webpack usage; it says the Angular component is out of date. · mergely.com, 8 Oct 2026
- Language highlighting
- Syntax highlighting for different languages is not supported out of the box, but language modes can be added when compiling a custom version. · mergely.com, 8 Oct 2026
- Licensing
- Mergely is distributed under GPL, LGPL, and MPL open source licenses, with a CDL available by contacting the maker. · mergely.com, 8 Oct 2026
- Merge controls
- The API can merge a whole document or the current change from one side to the other. · mergely.com, 8 Oct 2026
- Purpose
- Mergely is a browser based diff and merge editor and JavaScript library for comparing and merging text. · mergely.com, 8 Oct 2026
- Sharing
- Saved diffs are public to anyone with the link, who can view and manage the share. · editor.mergely.com, 8 Oct 2026
- Support
- The maker directs users to GitHub issues for support, and the CDL includes one year of personal email support. · mergely.com, 8 Oct 2026
- Supported browsers
- The maker lists Firefox, Chrome, Edge, and Safari as supported HTML5 compatible browsers. · mergely.com, 8 Oct 2026
Where Mergely stands on Freedom251
- File Comparison Software#8 of 33
- Diff and Merge Tools#12 of 29