Writing and content decision
Cleanpaste.org
A single competent developer can build and maintain a useful replacement in a weekend; the product's main durable advantage is brand/trust (public user base) which isn't a technical barrier to reproduction.
Visit website↗Built by 两万焦, who ships 8 products in this index
Not priced
No pricing page we fetched carried a figure, so there is nothing to compare against. The build side is still real.
$20one-off9 h to build
$0/mo1 h/mo upkeep
No published price to break even against.
Open-source builds that already do this
Every project below is open source and already does this job today. Fork one, self-host it, or take the parts you need - the build prompt further down assumes an empty file, and this is the shortcut past that. Licences differ; check the one on each card before you ship. All Cleanpaste.org alternatives, with the arithmetic →
What a replacement has to do
- User pastes text -> detect invisible characters/AI watermark patterns -> strip/normalize characters -> return cleaned text for copy/export
What it still won’t have
- Large existing user base and public traffic/brand (trusted by many users)
- Hosted, polished UX and possible cross-device reliability of the official site
- Any proprietary heuristics the vendor may have for watermark removal (if they exist)
What remains hard
- Brand trust
Trusted by 480,000+ users
First-year cost
No published price
Cleanpaste.org does not publish a price we could read, so there is nothing to compare against. What building costs is below.
Money you would actually spend
Time you would spend
—
What you would spend
What we assumed
The verdict above measures whether you could build it. This one is only about money.
Runnable build prompt
Build a single-page AI Text Cleaner using React for the frontend and a serverless function (Node.js on Vercel or Cloudflare Workers) for processing. In scope: (1) paste/textarea UI with character & word counters, (2) a text-cleaning module that detects and removes zero-width characters, zero-width joiners, non-printing Unicode, hidden metadata markers, and common AI-watermark patterns (implement as well-documented regexes and Unicode normalization), (3) endpoint to accept text and return cleaned text, (4) copy-to-clipboard and download (.txt) features, (5) unit tests for the cleaning functions and basic integration tests, (6) error handling and input validation. Out of scope: AI-detector integrations requiring third-party paid APIs, user accounts, analytics beyond basic logs, and bulk file uploads. Provide CI to run tests and a deployment script to publish to Vercel (or equivalent).
How we checked
How the score was reached
- Build verdict base78
- An open-source build was found+5
- 3 cited sources+3
- 3/3 assessment runs agreed+4
- Evidence score90
The base comes from the verdict. Everything under it is a check that either happened or did not, and each one is a fact frozen in this record rather than a judgement made at render time - so the same evidence always produces the same number.
How scoring works →Cited sources · 3
Every page the run actually retrieved.
- official productClean Paste - Remove Invisible Characters & AI Watermarks
- official pricingClean Paste is Free | Clean Paste
- open sourceavoid-ai-writing
Integrity checks
What held up, and what did not.
