Prompt Engineering

Text Diff Checker

Paste two texts and see exactly what changed — a git-style colored diff with additions, deletions, and word-level edits, and a mechanical change count.

Open in AI Text Diff Checker

Overview

When two versions of a paragraph look almost the same, the differences hide in plain sight. A diff checker surfaces them: this loads an edited paragraph and its revision, then shows every change line-by-line with the exact words that moved highlighted inline. It reports what changed and nothing more — no quality score, no verdict on which version is better. For what a prompt revision means, the Prompt Version Diff; for which prompt wins, the Prompt Comparator. This one just shows the difference.

How to use this resource

Paste both versions

Original on the left, changed on the right.
Read the colored diff

Additions green, deletions red, word edits highlighted inline.
Trust the count

A mechanical tally of lines and words that moved — no judgment.

Why This Works

A colored diff makes hidden changes between near-identical texts obvious
Word-level highlighting pinpoints exactly which words moved
The count is mechanical — what changed, never whether it is better

Best for

Spotting changes between two versions
Reviewing an edit before accepting it
Any two texts you need to compare

Not for

Judging which version is better — that's the Prompt Comparator
Interpreting a prompt revision's meaning — that's the Prompt Version Diff

FAQ

How do I see word-level changes between two near-identical paragraphs?

Mixed mode reports the edits inside each changed line, not just whole-line swaps. The MODIFIED CONTENT block shows '~ old:' / 'new:' pairs — 'Reports can be exported as PDF' becoming 'PDF or CSV', and 'simple chart' becoming 'clear chart of completed and pending tasks' — so the words that moved are pinpointed. The count reads 'Words: 11 inserted, 4 deleted'.

Does this diff checker say which version is better?

It does not — the count is mechanical, never a judgment. The NOTE states it shows 'what changed, not what it means or which text is better', and the tally ('+0 -0 ~3 lines, +11 / -4 words') carries no verdict. For what a prompt revision means use the Prompt Version Diff; for which of two prompts wins, the Prompt Comparator.

Customize This Resource

Opens both texts in AI Text Diff Checker. Compare to see the colored diff and the change summary — then adjust the diff mode.

Open in AI Text Diff Checker

Prompt Template

Copy it as-is, or use Open in AI Text Diff Checker to load it pre-filled and customize it with your own context.

TEXT DIFF REPORT

DIFF SUMMARY
- Mode: Mixed (line + word)
- Lines: 0 added, 0 removed, 3 changed
- Words: 11 inserted, 4 deleted

ADDED CONTENT
- (no fully added lines)

REMOVED CONTENT
- (no fully removed lines)

MODIFIED CONTENT
~ old: Our new dashboard helps teams track their weekly progress.
  new: Our redesigned dashboard helps teams track their weekly progress at a glance.
~ old: It shows a simple chart of completed tasks.
  new: It shows a clear chart of completed and pending tasks.
~ old: Reports can be exported as PDF.
  new: Reports can be exported as PDF or CSV.

UNIFIED DIFF
- Our new dashboard helps teams track their weekly progress.
+ Our redesigned dashboard helps teams track their weekly progress at a glance.
- It shows a simple chart of completed tasks.
+ It shows a clear chart of completed and pending tasks.
- Reports can be exported as PDF.
+ Reports can be exported as PDF or CSV.

STATISTICS
- Text A: 3 lines · 23 words · 134 characters
- Text B: 3 lines · 30 words · 171 characters
- Changes: +0 -0 ~3 lines, +11 / -4 words

NOTE
- This is a mechanical diff: it shows what changed, not what it means or which text is better.
- For what a prompt revision MEANS (improvement or regression), use the Prompt Version Diff; for which of two prompts is BETTER, use the Prompt Comparator.

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AI Text Diff Checker

See exactly what changed between two texts — a git-style colored diff with added, removed, and word-level edits. Mechanical, no judgment.

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