Text Diff

Compare two texts and get a unified diff with change summary.

POST 1 credit /v1/diff

curl -X POST "https://devtools.toolkitapi.io/v1/diff" \
  -H "Content-Type: application/json" \
  -d '{"a": "hello world\nfoo bar", "b": "hello world\nfoo baz"}'

import httpx

resp = httpx.post(
    "https://devtools.toolkitapi.io/v1/diff",
    json={"a": "hello world\nfoo bar", "b": "hello world\nfoo baz"},
)
print(resp.json())

const resp = await fetch("https://devtools.toolkitapi.io/v1/diff", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
  },
  body: JSON.stringify({"a": "hello world\nfoo bar", "b": "hello world\nfoo baz"}),
});
const data = await resp.json();
console.log(data);

# See curl example

Response 200 OK

{
  "unified_diff": "--- a\n+++ b\n@@ -1,2 +1,2 @@\n hello world\n-foo bar\n+foo baz\n",
  "summary": {
    "lines_added": 1,
    "lines_removed": 1
  }
}

Try It Live

Description

Compare two texts and get a unified diff with change summary.

How to Use

1

1. Send a POST request with `a` (original text) and `b` (modified text).

2

2. The `unified_diff` field contains the full diff output. The `summary` gives line-level change counts.

About This Tool

Text Diff compares two text inputs and produces a unified diff output (the same format used by `diff -u` and Git). The summary tells you exactly how many lines were added and removed.

Why Use This Tool

Code review — Compare two versions of a file or snippet
Content tracking — Detect changes between document revisions
Config drift — Spot differences between environment configs
Testing — Assert that output matches expected text

Frequently Asked Questions

What diff format is used?

Standard unified diff format, identical to `diff -u` or `git diff`. Lines prefixed with `+` are additions, `-` are removals, and ` ` (space) are context.

Start using Text Diff now

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