Text generator

Random Character Inserter

Add random letters, numbers, symbols, or custom characters into text for dirty datasets, noisy file names, and testing workflows.

Runs Locally

This tool runs in your browser. Files never leave your device.

Original text

Generated text

Inserted 3 characters across 26 words.

Paste clean text here and cQhoose how many random characters to insert. This is utseful for building dirty datasets, noisy file namdes, and messy test strings.

Runs locally: your text stays in your browser.

Spread out: insertions are distributed across the input.

Customizable: letters, numbers, symbols, or your own set.

What this tool does

Random Character Inserter drops random letters, numbers, or symbols into your text to rough it up for testing. It is the quick way to create dirty input that exposes how a parser, validator, or cleaning routine handles unexpected characters.

How it works

Paste your text, choose what to insert and how often, and the tool generates the noised-up version in your browser. Copy the output as test data. Nothing is uploaded.

When to use Random Character Inserter

Testing input validation against junk characters

Creating dirty data for a cleaning routine to fix

Stress-testing a parser with unexpected symbols

Generating noisy samples for QA

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