Regex tester

What is a regex tester?

A regex tester lets you write a regular expression and immediately test it against sample text. Matches are highlighted in the text, and detailed information about each match — including captured groups — is shown alongside. It's the fastest way to iterate on a regex pattern without running your full application.

When to use a regex tester

• Writing a validation pattern for emails, phone numbers, URLs, or custom formats
• Debugging a regex that isn't matching what you expect
• Learning regex syntax by experimenting with different patterns and flags
• Extracting data from logs, CSVs, or unstructured text
• Building search-and-replace patterns for your editor or codebase

Common regex patterns

Some frequently needed patterns: \b\w+@\w+\.\w+\b for basic email matching, ^\d{4}-\d{2}-\d{2}$ for ISO dates, https?://[^\s]+ for URLs, and ^(?=.*[A-Z])(?=.*\d).{8,}$ for password validation with at least one uppercase letter and one digit.

Query your data without writing regex

If you're using regex to search through database records, Basedash offers a faster path. Describe the pattern you're looking for in plain English and Basedash generates the SQL or filter — no regex or manual queries needed. It connects to PostgreSQL, MySQL, MongoDB, and 750+ other data sources.