RegexVision API
Automate regular expression generation, optimization, and explanation in your own applications. Start building immediately with our Generous Free Tier.
No Key Required
The Free Tier does not require an API key to get started. Just point to the endpoint.
Rate Limited
Free tier is limited to 50 requests per hour per IP address to ensure fair usage.
Fast & Accurate
Powered by the same Gemini 2.5 Flash models that drive the web application.
POST/api/regexGenerate a regex from a natural language prompt.
Request Body
{
"action": "generate",
"input": "Match a valid IPv4 address"
}Response (200 OK)
{
"result": "^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$"
}POST/api/regexExplain a regular expression in plain English.
Request Body
{
"action": "explain",
"input": "^[a-z0-9_-]{3,16}$"
}Response (200 OK)
{
"result": "This regular expression matches a string that:\n\n1. **^**: Starts at the beginning of the string.\n2. **[a-z0-9_-]**: Contains only lowercase letters (a-z), numbers (0-9), underscores (_), or hyphens (-).\n3. **{3,16}**: Is between 3 and 16 characters long.\n4. **$**: Ends at the end of the string.\n\nIn short, it validates a username or identifier that is 3-16 characters long and contains only alphanumeric characters, underscores, and hyphens."
}