Frequently Asked Questions

Yes, TextCompare is completely free. There are no subscription plans, no premium tiers, and no account required. Every feature — including file upload, share links, all diff modes, and JSON comparison — is available to every visitor at no cost.

Your text never leaves your device. All comparison logic — tokenization, diff computation, highlighting, and rendering — runs entirely in your browser using JavaScript. There are no accounts, no server logs, and no analytics on your content. You can safely use TextCompare with confidential documents, source code, legal contracts, or any sensitive material.

No account or login is required for any feature. Open the tool, paste your texts, and compare — that is all. There are no cookies for tracking, no mandatory sign-ups, and no email walls.

TextCompare accepts any plain-text file. Common supported formats include: .txt, .md, .csv, .json, .xml, .html, .css, .js, .ts, .py, .rb, .java, .go, .yaml, .toml, .sql, .sh, and any other file that opens as readable text. Binary files such as PDFs, Word documents (.docx), Excel spreadsheets, or images are not supported. You can drag-and-drop files directly onto either input panel.

TextCompare offers three diff granularities: line mode (default — fastest, compares whole lines), word mode (useful for prose — highlights individual word changes), and character mode (most granular — every character change is flagged). You can also switch the view between side-by-side (two panels, good on wide screens) and unified (single column, Git-style, good on mobile).

When the diff detects two lines that are similar but not identical, it runs a second character-level diff pass on just those two lines. The result highlights the exact characters that changed — shown as a darker background within the already color-coded line. This lets you spot a single changed number or word in a long line without scanning the entire text.

Yes. The options bar above the comparison result includes checkboxes for Ignore Case, Ignore Whitespace, and Ignore Blank Lines. These pre-process the tokens before the diff runs, so cosmetic differences that do not affect meaning are not flagged as changes. All three can be combined.

Yes. For code comparisons use the dedicated Code Diff Checker, which is optimized for programming languages. It preserves indentation, handles line endings consistently, and defaults to a unified view that matches the git diff format developers are familiar with. It works with any programming language that stores source as plain text.

Yes. The JSON Diff Checker parses both inputs as JSON, sorts keys alphabetically, and normalizes indentation before diffing. This means reformatted JSON — where only whitespace or key order changed — does not show false positives. Only actual value changes are highlighted.

No server storage is involved. When you click Share, both texts are gzip-compressed using the browser's CompressionStream API and encoded as Base64url, then appended to the page URL as a query parameter. The link recipient's browser decodes and decompresses the texts locally. TextCompare's servers never see the content — only the HTML, CSS, and JS files are served from the server.

There is no enforced text limit for pasted content. File uploads are capped at 10 MB per file to prevent accidental browser slowdowns. In practice, files up to 100 KB compare nearly instantly. Files of 1 MB+ may take several seconds on slower devices but the UI stays responsive due to scheduled rendering. For the share URL, very large texts may produce URLs that exceed browser limits (~2 MB); TextCompare will warn you if this happens.

TextCompare works in all modern browsers: Chrome 120+, Firefox 121+, Safari 17+, Edge 120+, and their mobile counterparts. The share URL feature requires the CompressionStream API, which is supported in all current browsers. Internet Explorer is not supported. If you are on an older browser, the diff itself will work but sharing may not.

TextCompare supports the following keyboard shortcuts:

• Ctrl+Enter — Run comparison
• n — Jump to next change
• p — Jump to previous change
• ? — Open keyboard shortcuts panel
• Esc — Close modal / panel

For the full reference, press ? while on the comparison page or visit the Help page.

Yes. The results toolbar includes a Download button that saves the diff as a plain-text unified diff file (.diff or .patch format). You can also copy the diff output directly from the results panel using standard keyboard shortcuts.