Text Diff API — IteraTools

About this tool

Compare two text inputs and get a structured diff showing additions, deletions, and unchanged content. Choose between three output formats: unified (standard patch format), json (line-by-line structured array), or inline (word-level comparison). Includes stats on additions, deletions, and whether texts are identical. Runs entirely locally — no external API calls.

Quick Start — Unified Diff

curl -X POST https://api.iteratools.com/text/diff \
  -H "Authorization: Bearer YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "text1": "Hello world\nThis is the original text\nLine three",
    "text2": "Hello world\nThis is the modified text\nLine three\nNew line four",
    "format": "unified"
  }'

Response (Unified)

{
  "ok": true,
  "data": {
    "format": "unified",
    "identical": false,
    "diff": "Index: text\n===...\n-This is the original text\n+This is the modified text\n Line three\n+New line four",
    "stats": {
      "additions": 2,
      "deletions": 1,
      "unchanged": 2,
      "total_changes": 3
    }
  }
}

JSON Format Example

curl -X POST https://api.iteratools.com/text/diff \
  -H "Authorization: Bearer YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{"text1": "line one\nline two", "text2": "line one\nline three", "format": "json"}'

{
  "ok": true,
  "data": {
    "format": "json",
    "identical": false,
    "diff": [
      { "type": "unchanged", "value": "line one\n", "lines": 1 },
      { "type": "removed", "value": "line two", "lines": 1 },
      { "type": "added", "value": "line three", "lines": 1 }
    ],
    "stats": { "additions": 1, "deletions": 1, "unchanged": 1, "total_changes": 2 }
  }
}

Parameters

text1 (required) — Original text (max 100KB)
text2 (required) — Modified text (max 100KB)
format (optional) — Output format: unified (default), json, or inline

Output Formats

unified — Standard patch format (like git diff). Returns a string.
json — Line-by-line structured array. Each element has type (added/removed/unchanged), value, and lines count.
inline — Word-level comparison. Each element has type and value. Great for highlighting changes within lines.

Response Fields

format — The format used (unified/json/inline)
identical — Boolean, true if texts are exactly the same
diff — The diff output (string for unified, array for json/inline)
stats.additions — Number of added lines/words
stats.deletions — Number of removed lines/words
stats.unchanged — Number of unchanged lines/words
stats.total_changes — Total changes (additions + deletions)

Use Cases

Track changes between document versions in AI workflows
Compare LLM outputs across different prompts or models
Build version control features into content management systems
Detect plagiarism or content drift in web scraping pipelines
Validate code transformations and refactoring results
Generate change summaries for review workflows

Pricing & Limits

$0.001 per request via x402 micropayment on Base (USDC)
Max text size: 100KB per field
No external API calls — instant response

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