Forbidden Word Checker

Find and highlight forbidden words in text based on a user-provided list.

Category: Text Tools

When to use?

Use it to test forbidden-word filter logic when building a community service or chatbot, or to check whether a post contains certain words before publishing.

How to use

  • Enter the forbidden-word list, one per line.
  • Enter the text to check.
  • Found words and their positions are highlighted.

Input Explanation

Enter the forbidden-word list (one per line) and the source text to check.

Calculation Basis

It searches each word from the list, collects start/end positions in the text, and highlights matches. With case-insensitive on, only the comparison string is lowercased.

Usage Examples

  • Test a word filter - Check whether a service's forbidden-word list is detected correctly.
  • Pre-review posts - Quickly check whether text contains banned words before publishing.
  • Pre-check comments - Check whether a comment contains banned expressions before posting.

Examples

  • Add a word to the list → it is highlighted wherever it appears in the text
  • Register several words → all matched words in a post are highlighted

Cautions

  • The word list and results are processed only in the browser and not sent to a server.
  • Counts can vary by how spaces and line breaks are handled.

FAQ

Is it case-sensitive?

Choose the case-insensitive option to check regardless of case.

Is the word data stored?

No. All processing happens only in the browser.

How do I enter the word list?

Enter your reference words and the tool finds and marks them in the text.

Are partial matches caught?

A forbidden word is detected if it appears as a substring of the text.

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