A free tool by Nina Kolari

Remove invisible characters from AI text.

A free AI text cleaner for Claude, ChatGPT and everyday copy-and-paste. Remove zero-width spaces, review what changed and copy your cleaned text. No account. Text stays on your device.

Looking to remove a Claude watermark? This tool cleans hidden characters, but does not remove Claude’s statistical text watermark. Learn the difference.

Before cleanup

Here's a quick summaryzero-width space of the Q3 plan.narrow no-break space The team shipped the featurezero-width space ahead of schedule.byte order mark

Cleaned

Here's a quick summary of the Q3 plan. The team shipped the feature ahead of schedule.

3 hidden characters removed · 1 unusual space normalized

Example with whitespace normalization enabled.

Clean your text

The result updates as you type. Review it before copying.

Original text

Cleaned text

Cleanup settings

Cleanup options

Hidden-character cleanup is on. Spacing and punctuation changes are optional. Joiners and emoji tag sequences are preserved unless aggressive cleanup is enabled.

Remove unwanted hidden characters zero-width spaces, word joiners, byte order marks and stray Unicode tags; keeps joiners and directional controls by default Normalize whitespace non-breaking & unusual spaces → normal space, trim line ends, collapse 3+ blank lines, CRLF → LF Replace “smart” punctuation curly quotes → straight, … → ..., —/– → - (approximate) Aggressive character cleanup Also removes joiners, directional controls and emoji tags. Can change emoji, language rendering and mathematical notation. Re-encode images to remove source metadata JPEG, PNG and WebP only. Re-encoding can change quality, colour and file size; animation becomes a still image.

Clean files

Plain .txt files use your settings. Structured files (Markdown, code, CSV, JSON and subtitles) only lose an initial BOM; other content is preserved. Text must be UTF-8. Choose files again after changing settings.

Images: up to 20 MB and 20 megapixels each. Re-encoding discards source metadata and can change quality, colour and size. Animated PNG/WebP become still images. Visible logos and pixel-based watermarks are not removed.

Drop files here, paste an image, or click to choose
Text files (.txt .md .csv .json .html .xml .srt .vtt …) and images (.jpg .png .webp)

Under the hood

What it takes out.

Hidden characters

Default cleanup removes zero-width spaces, word joiners, byte order marks and stray Unicode tags. Joiners, directional controls and emoji tag sequences are preserved; aggressive mode removes them.

Whitespace tricks

Optional normalization converts unusual spaces and line endings, trims trailing spaces and reduces long blank runs. Leave it off to preserve Markdown hard breaks and spacing.

File metadata

JPEG, PNG and WebP are decoded and saved as new images rather than copying source metadata such as EXIF or GPS. Review the exported file before sharing sensitive images.

Hidden characters are not proof of AI authorship. Some have legitimate language and formatting uses. Review changes before using the result.

Choose the right cleanup

When to use this AI text cleaner.

Remove zero-width spaces

Use the invisible-character remover when copied text contains unwanted zero-width spaces or stray formatting marks. The report names each removed character and its Unicode code point.

Clean Claude or ChatGPT text

Prepare pasted text for a document, email or website. Start with default cleanup, then turn on spacing or punctuation changes only if you need them. This does not rewrite your text.

Remove image source metadata

Re-encode a JPEG, PNG or WebP locally without copying its source metadata. Review image quality before sharing. See formats and limitations.

What we tested

Our regression tests check emoji such as 👩🏽‍💻 and ❤️‍🔥, Indic and Persian joiners, Markdown hard breaks, structured-file preservation and a large text sample. Default cleanup preserves those tested sequences; aggressive mode intentionally does not.

Read the actual tests on GitHub · Compare a text cleaner, watermark remover and AI rewriter

What this tool can do

AI watermark questions, answered.

Can this remove a Claude AI watermark?

No. Claude’s documented text watermark is a statistical pattern in word choices, not hidden Unicode characters. This tool cleans formatting. Read the Claude AI watermark guide.

Are invisible characters an AI watermark?

Not necessarily. Invisible characters also occur in ordinary documents, language shaping and copy-and-paste formatting. Finding one does not identify an AI author.

Will this change an AI detector’s result?

There is no guarantee. The cleaner does not rewrite your words or test statistical watermarks, and its report is not an AI-detection score.

Can cleanup change emoji or formatting?

Default cleanup preserves joiners and emoji tag sequences. Aggressive cleanup can break these sequences. Optional spacing cleanup removes Markdown hard breaks; punctuation replacement can change meaning. Review the output.

Does my text leave my browser?

The cleaner processes text and files locally without sending their contents to a server. This page loads fonts from Google, and the host receives normal page requests. Privacy and limitations.

Can I remove a watermark from an image?

This tool re-encodes supported images to discard source metadata. It does not erase visible watermarks or promise removal of marks encoded in the pixels. Image metadata removal explained.