Calculator
What the Text Diff Checker does
Text Diff Checker: checks its result instantly in your browser, with no signup and nothing sent to a server. Example: the sample loaded on the page gives summary 2 added, 2 removed, 0 unchanged.
Feed it Original and Changed; it hands back a side-by-side comparison with the changed words marked. Adjust anything and the figures re-derive on the spot.
Most people who open the Text Diff Checker are anyone reformatting pasted text. Text pasted from another program usually arrives with formatting nobody wants.
There is no account, no upload and no server round trip, because the page does the work itself.
Below the tool you will find the field reference, the method, and an example computed from the values it opens with.
What do the Text Diff Checker fields mean?
The Text Diff Checker uses 2 inputs. The page opens in a usable state: real values in, real answer out, ready to edit.
| Field | What to enter | Default |
|---|---|---|
| Original | paste or type any amount of text | The quick brown fox jumps over the lazy dog |
| Changed | paste or type any amount of text | The quick red fox jumps over the lazy cat |
How does the Text Diff Checker work?
Each output is derived from the inputs above in a single pass; there is no hidden state carried between runs, so the same inputs always give the same check.
Bad input produces an error, never a confident-looking wrong answer.
Worked example
These are the values the Text Diff Checker loads by default, and the result it produces from them. Below is the same computation the tool performs on load, step by step.
| Original | The quick brown fox jumps over the lazy dog |
|---|---|
| Changed | The quick red fox jumps over the lazy cat |
| Summary | 2 added, 2 removed, 0 unchanged |
|---|
How to use it
- Paste your content into Original.
- Paste your content into Changed.
- No submit step is needed; the output updates while you edit.
- Look at Summary in the output panel.
- Copy Link when you want to return to this exact configuration; Print when someone needs it on paper.
What this tool does not do
- Word and character definitions vary between tools: this one counts whitespace-separated tokens.
- Very large pastes are limited by your browser memory rather than a server quota.
- There is no history: reload the page and the previous run is gone.
Frequently asked questions
You need Original and Changed. Every box already holds a working value, so the quickest approach is to replace the one number you actually care about.
With the values loaded when the page opens, summary comes out as 2 added, 2 removed, 0 unchanged. Adjust any field to see how much the answer depends on it.
No. Disconnect from the internet and it still works; that is the simplest proof there is no server call.
No charge. Everything on the page is available without signing in.
The computation is exact; how much you should trust the answer depends on how good your inputs are.