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Text Diff

Compare source, configuration, logs, or arbitrary text with focused line-by-line changes.

Runs locally — input is never uploaded
Paste, type, or drop text
Paste, type, or drop text
ChangesReady when you are
Changed lines will appear here

WHAT IT DOES

A focused line diff for everything that is not a JSON structure.

Compare two text documents exactly as they are written, whether they contain source code, configuration, logs, generated output, or prose. The result groups changed regions into side-by-side hunks with original and updated line numbers while keeping a small amount of unchanged context around each one. A second action ignores runs of whitespace when indentation or wrapping would otherwise hide the changes that matter.

Why use it?

Use a line comparison for logs, prose, and configuration where comments, ordering, and written text matter—not just parsed values.

How to use this tool

  1. Put the earlier text in Original and the later text in Updated, then compare.
  2. Read the changed regions with their line numbers and surrounding context. Switch to Ignore whitespace only when spaces and tabs are irrelevant to the question.
  3. For indentation-sensitive configuration or source, also review the exact comparison: whitespace-tolerant matching can hide a meaningful change.

Details and limitations

  • Insertions, deletions, and replacements are aligned by unchanged lines and displayed with their original source line numbers.
  • The whitespace-tolerant comparison trims each line and collapses internal whitespace for matching, while the displayed text remains byte-for-byte readable.
  • The alignment pass is bounded for large files and falls back to a linear comparison rather than allocating a matrix proportional to the full input.
  • One or two local text files can be dropped onto the document panes, with a 10 MiB limit per rendered file.

COMMON QUESTIONS

Text Diff questions

When should I use JSON Diff instead?
Use JSON Diff when key order and formatting should not count as changes. Text Diff compares written lines, so indentation, order, and comments are meaningful unless the whitespace-tolerant action is selected.
What does Ignore whitespace change?
It trims each line and treats consecutive spaces and tabs as one space while finding matches. The result still shows the original text, so indentation differences remain visible without causing every affected line to become a separate mismatch.