🕵️ Invisible Text Generator – Hide Messages in Plain Sight
The Invisible Text Generator lets you embed secret messages inside perfectly normal-looking text using invisible Unicode zero-width characters. The output appears visually unchanged — readers see only your carrier text — yet anyone with the decoder can extract the hidden payload. This technique is called text steganography.
How Zero-Width Character Encoding Works
Every character in your secret text is converted to its Unicode code point, then represented as a 21-bit binary number. Each bit is mapped to an invisible character:
| Bit | Unicode | Name |
|---|---|---|
0 | U+200B | Zero Width Space |
1 | U+200C | Zero Width Non-Joiner |
| BOM | U+FEFF | Zero Width No-Break Space (start marker) |
| End | U+2063 | Invisible Separator (end marker) |
For example, encoding the letter A (code point 65, binary 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 1) produces 21 consecutive invisible characters, indistinguishable from whitespace to the human eye or a casual copy-paste.
Five Operating Modes
🔒 Encode
Embed a hidden message inside a visible carrier text. Choose to inject the invisible payload at the start, end, or at a custom character index within the carrier.
🔓 Decode
Paste any text — even text that appears completely normal — to extract and reveal any hidden zero-width character payload encoded with this tool.
👻 Pure Invisible
Generate a string that looks completely blank but contains the fully encoded secret. Useful for embedding hidden metadata in form fields, usernames, or social media bios.
🔏 Watermark
Distribute a unique fingerprint token invisibly across all word boundaries of a document. Each recipient copy carries a different watermark, enabling leak detection and plagiarism tracking.
🔍 Inspector
Scan any pasted text for invisible Unicode characters. The inspector reports every zero-width code point found, along with its Unicode name, position, and hex value — even if no recognizable encoding scheme is present.
Common Use Cases
- Text steganography — Hide a secret message inside a tweet, email, or document without changing its visual appearance.
- Digital watermarking — Embed a unique recipient ID in each copy of a confidential document to trace unauthorized leaks.
- Hidden annotations — Attach metadata or comments to plain text that standard readers won't display.
- Security research & education — Learn how Unicode invisible characters work and how content-filtering tools can be bypassed or how to detect such techniques.
Limitations & Security Considerations
Zero-width steganography is not encryption. The hidden payload is not protected by any cryptographic key — anyone using this decoder (or any Unicode-aware tool) can extract it. Additionally:
- Many email clients, word processors, and sanitizers strip zero-width characters automatically.
- Security scanning tools flag zero-width characters in URLs and filenames as potentially malicious.
- The technique is easily defeated by copying text and running it through a sanitizer that removes non-printable characters.
For confidential communications, always use end-to-end encryption. This tool is best suited for watermarking, educational exploration, and lightweight content tagging.
Payload Size Guide
Each character of your secret text produces 21 invisible characters in the output (for full Unicode coverage). A 10-character secret generates ~210 zero-width characters; a 100-character secret generates ~2,100. The tool warns you when the payload exceeds 200 characters, as very large payloads may be truncated on some platforms. The maximum allowed secret length is 500 characters.
BOM Marker
Enabling the BOM Marker option prepends a U+FEFF (Zero Width No-Break Space) before the encoded payload. This acts as a recognizable header so your own decoder can quickly locate and validate the start of an encoded sequence in longer texts.
Inspector: Detecting Hidden Characters
The Inspector mode scans text for all 14 recognized invisible Unicode code points in the ranges U+200B–U+200F, U+FEFF, U+2060–U+2064, and U+FFF9–U+FFFB. It returns each match with its exact character position, Unicode hex code, and official Unicode name — making it a useful tool for content moderation, security audits, and verifying that text has been sanitized.
💡 Pro Tip
Combine the Watermark mode with a unique per-recipient token before distributing a confidential document. If the document leaks, use the Decode mode on the leaked copy to instantly identify which recipient was the source.