YAML Diff — Compare YAML Files Online
Online YAML Diff — fast and accurate difference checker for YAML. Paste two files and instantly see highlighted differences for Kubernetes and DevOps configs.
| L | Left | R | Right |
|---|---|---|---|
| - | name: Alice | ||
| ~ | age: 30 | ~ | name: Alice B. |
| + | age: 31 | ||
| + | city: Paris |
What this tool does
This page compares two documents and highlights what changed—added lines, removed lines, and modified lines—so you can review API responses, configuration files, and data snapshots quickly and safely. It supports JSON, YAML, and XML, plus plain text. Choose Side-by-Side or Unified view, copy a patch-style diff, and share a read-only link with teammates.
How the diff works (high level)
We use a longest common subsequence (LCS) algorithm for line-level comparison, then apply a lightweight character-level diff inside changed lines. That gives you a concise view of structural edits (new/removed lines) and the exact characters that changed—useful for spotting typos, renamed keys, and subtle value changes.
Step-by-step
- Paste or drop your Left and Right files.
- (Optional) Keep Auto-detect & Beautify on to normalize indentation and spacing before diffing.
- Click Run Diff (or press Ctrl+Enter).
- Switch between Side-by-Side and Unified views to match your workflow.
- Copy the unified diff or generate a shareable link for quick reviews.
Color legend
- – (deletion): content present in Left but not in Right.
- + (addition): content present in Right but not in Left.
- ~ (change): same line exists, with character-level highlights for differences.
Tips for JSON, YAML, and XML
- JSON: Normalize arrays/objects with Beautify so key ordering is consistent across files.
- YAML: Indentation is semantic—use spaces, not tabs. Quoting scalars like
on/offprevents unintended booleans. - XML: Pretty-printing can reorder attributes or whitespace. If you need a raw textual diff, turn off Auto-beautify.
Common use cases
- Reviewing API response changes between two builds.
- Comparing Kubernetes/CI YAML revisions before deploy.
- Checking partner XML payload differences during integrations.
- Auditing config drift across environments.
Performance & privacy
All processing happens in your browser—no uploads, no logging, no storage. This keeps sensitive configs and payloads private while providing instant feedback even on slow connections.
Keyboard shortcuts & accessibility
- Ctrl+Enter → Run Diff
- Ctrl+/ → Swap Left/Right
- Tab-focusable controls and ARIA roles on segmented view for better screen-reader support.
Troubleshooting
- “Nothing changed?” Ensure line endings are normalized; Beautify usually helps.
- Unexpected XML changes: Disable Auto-beautify for byte-level comparison.
- Large files: Diff in sections or strip non-essential whitespace first.
Need to validate or convert before comparing? Try our Validator and Converter tools, then return here for a clean diff.
FAQ
- What file types can I compare?
JSON, YAML, and XML are first-class. Any plain text (e.g., .txt, .log, .conf) also works.
- How do I run a diff quickly?
Paste or drop files into Left and Right, then click Run Diff or press Ctrl+Enter.
- What's the difference between Side-by-Side and Unified view?
Side-by-Side shows left and right panels aligned. Unified shows a single patch-style view with + (add), - (delete), and ~ (change).
- What do the symbols +, -, and ~ mean?
+ indicates additions, - indicates deletions, and ~ highlights changed lines with character-level differences.
- How are differences calculated?
We use a longest common subsequence (LCS) at the line level, then a lightweight character-level diff within changed lines.
- Why do I see changes even though the data looks the same?
Whitespace, indentation, and line endings (CRLF vs LF) can differ. Enable "Auto-detect & Beautify before diff" to normalize, or disable it for a raw, byte-like comparison-especially for XML.
- Can I ignore whitespace or key ordering?
There's no dedicated ignore-whitespace toggle, but Beautify reduces whitespace noise. JSON key order isn't guaranteed by spec, so normalize both sides before diffing.
- How do I swap Left and Right quickly?
Use the swap button or press Ctrl+/. It's handy when a patch looks reversed.
- Can I share the diff with a teammate?
Yes. Use "Copy shareable link". The inputs are encoded in the URL hash (not uploaded) so others can open the same diff.
- Can I export or copy the diff result?
Yes. Use Copy unified diff to get a patch-style output you can paste into reviews or tickets.
- Will comments be preserved?
JSON doesn't support comments. YAML/XML comments may not survive normalization. Treat this as a data diff, not a comment-preserving tool.
- Does it support folder diffs or binary files?
No-this tool focuses on text-based diffs for JSON, YAML, XML, and other plain text.
- Is my data uploaded to a server?
No. All tools run locally in your browser; your data isn't sent to any server.
- Can I use the tool offline?
After the page loads once, most browsers will allow basic offline usage because processing is entirely client-side.
- Can I beautify JSON?
Yes - use the Beautify actions in each tool where applicable.
- Do you keep my files?
No. All tools run locally in your browser; data is not uploaded to any server.
- Is there a size limit?
Large inputs are limited by your browser memory; for most cases typical files work fine.
- Is it free?
Yes, All tools are 100% free and no sign-up required.