Diffchecker
Paste two blocks of text and get a colour-coded diff back immediately. Also handles PDFs, images and spreadsheets.
Opens in a new tab. We do not control this site and it may have changed since we catalogued it.
How to get the most from it
Diffchecker sits in Unreasonably Useful under Learn, filed as instant.
- Just open it. It pays off within seconds, with nothing to read first.
- Use a laptop or desktop computer — we file it as desktop only.
- It works with the sound off, so it is fine on a train or in a quiet office.
- No account needed — you can start without signing up.
- Go in expecting something useful.
About this category: Sites that quietly do a job you would otherwise pay for or install software for. Included because being this good for free is genuinely strange.
Good for
- A five-second distraction
- Getting something practical done
- A quiet break at your desk
- Trying it with zero commitment
Diffchecker: quick answers
Is Diffchecker free?
Yes. Diffchecker is free to use and needs no account.
Do I need an account to use Diffchecker?
No. You can use Diffchecker without signing up for anything.
Does Diffchecker work on a phone?
Not well. We file Diffchecker as desktop only, so open it on a laptop or desktop computer.
Is Diffchecker safe for work?
Yes, we file it as safe for work. It also works muted.
How long does Diffchecker take?
We file it as "Instant": Good within five seconds of loading.
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