Code diff
The code review view for code that never met a repository: two versions side by side, changes aligned, formatter noise switchable off.
Guide
How to use it
- Paste your version left, the other version right.
- The side-by-side view aligns changed lines in pairs, replacements read across the row.
- Formatter touched everything? Tick ignore whitespace to see only logic changes.
- Switch to inline for a unified, top-to-bottom read.
Examples
Worked examples
A bug report includes "the code we run". Diffing it against the actual deployed file shows the reporter's copy is two releases old, mystery solved before debugging starts.
A supplier ships v2.4 of a script you patched locally. The diff shows exactly which of your changes their update overwrites before you deploy it.
Staging and production nginx configs, pasted side by side with ignore whitespace on: one proxy timeout differs. That is the outage.
Method
How it works
Lines are aligned with a longest-common-subsequence diff, the algorithm family behind git. In the side-by-side view a removal followed by an addition is paired into one row, which is how a human reads a replacement. Ignore-whitespace normalises indentation before comparing but displays your code exactly as pasted, monospace, wrapping long lines rather than truncating them.
Your code is compared on your device and never uploaded.
FAQ
Frequently asked questions
When would I diff code here instead of in git?
When the two versions never lived in the same repository: a snippet from a ticket versus production, a vendor's new release versus your patched copy, or config pulled from two environments.
How do I stop indentation changes swamping the diff?
Tick ignore whitespace. Lines that differ only in indentation or spacing then count as unchanged, leaving the logic changes visible.
Does it understand syntax?
It compares lines as text in a monospace view, which is what most code review reading actually needs. It does not parse the language, so a renamed variable shows on every line it touches.
Can it produce a patch file?
Not yet. The inline view reads like a unified diff, but export in .patch format is on the roadmap.
Is pasting proprietary code here safe?
The comparison runs on your device and nothing is transmitted, which you can verify offline. That is the difference from paste-to-server diff sites.
What is the size limit?
Roughly 2,000 lines per side stays instant. Bigger files: split by function or section, or use a local tool for whole-repository work.
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