Diff Checker
Compare text, JSON files, YAML files, screenshots, SVGs, and local folders online with side-by-side or inline diff views plus a private visual image diff suite. Ignore whitespace, ignore case, scan changed files, and compare everything with 100% browser-side processing.
Shortcuts: Ctrl/Cmd + Enter compares, Escape clears both panels, and J / K jump between change blocks after you run a diff. Press / to focus diff search, then use Enter or N for the next match and Shift + Enter or Shift + N for the previous one. O keeps the original block, M keeps the modified block, and B keeps both versions in the merge preview. Enable Live compare for inline editing feedback, use the Change map to jump through long diffs faster, or keep Live compare off when you are pasting very large files. Large comparisons move to a background worker automatically so the page stays responsive. Saved drafts stay in this browser only, and Copy share link creates a URL hash you can send for snippet-sized comparisons.
Folder compare
Compare two local folders privately
In Chrome and Edge, you can pick two local folders, scan which files changed, then open any changed text file in the diff viewer below. Nothing gets uploaded.
Best in Chromium browsers with the File System Access API.
Original folder
Modified folder
Pick two folders to compare project-level changes locally in your browser.
Visual image diff
Compare screenshots, SVGs, and design exports privately
Upload two screenshots, UI exports, logos, or SVG files to spot pixel-level changes without sending anything to a server. Use overlay, swipe, and heatmap views to audit visual regressions locally in your browser.
Best for PNG, JPG, WebP, GIF, BMP, and SVG files.
Original image
Modified image
Upload two images or SVGs to open a private visual diff workspace.
Resolve changes locally
Why use this diff checker?
This diff checker is built for fast, private comparisons. You can compare source code, JSON, YAML, SQL, Markdown, config files, and plain text without uploading anything to a server. When formatting noise gets in the way, turn on Ignore whitespace or Ignore case to focus on meaningful edits.
When to use side-by-side vs inline diff
Side-by-side view is best when you want to inspect both versions line by line, especially for code review and config changes. Inline view is better when you want a compact, unified diff for quick scanning, documentation, or sharing in tickets and pull requests.
Common use cases
- Compare two JSON API responses after a backend change
- Review YAML files for Kubernetes, Docker Compose, or CI pipelines
- Spot changes in .env values, app configs, or infrastructure templates
- Compare SQL queries, migration scripts, or generated code output
- Check revised copy, legal text, contracts, or product descriptions
- Verify generated output against an expected result before shipping
Compare JSON files, YAML files, plain text, and local folders
If you need a private JSON diff checker or YAML diff checker, this page is designed for that workflow. Paste both versions or upload plain-text files, then switch between side-by-side and inline views to inspect API payloads, Kubernetes manifests, config files, Markdown, logs, and other text-based formats.
In supported Chromium browsers, you can also compare two local folders and get a file-by-file map of what changed. That makes it useful for release folders, exported configs, generated docs, and source trees where you want a quick project-level answer before drilling into a single file diff.
Turn on automatic syntax highlighting to color JSON keys, YAML fields, HTML tags, and SQL keywords. That makes schema changes, config edits, and query revisions easier to scan without leaving the browser.
Privacy and accuracy
All comparison runs in your browser using JavaScript. Nothing is uploaded. That makes this tool a good fit for internal code, secrets-adjacent configuration, and any text you would rather not paste into a cloud service.
You can also upload plain-text files such as JSON, YAML, HTML, SQL, Markdown, logs, and config files, then download or copy a unified diff report when you need to attach changes to a ticket or review.
For example, you can compare production and staging config snapshots, inspect two exported API payloads, or review a generated policy document without sending any of it to a third-party server.
Merge text changes without leaving the browser
After you compare both versions, the merge workspace lets you keep the original lines, keep the modified lines, or keep both for each change block. That is useful when you are resolving config conflicts, combining generated output with manual edits, or assembling a final revision before you paste it back into your editor.
The merged preview updates locally in real time and can be copied, downloaded, or loaded back into the modified panel for another comparison pass.
Save drafts or compare live while you type
Enable Remember draft to keep both text panels, compare options, and your chosen view mode in this browser between sessions. Turn on Live compare when you want immediate feedback while editing JSON, YAML, configs, and code samples.