A CLEARER WAY TO COMPILE PATTERNS

Write the rule.
Read the regex.

Write clear rules. Inspect the regex. Test real examples.

THE INPUT ✍️

Write your rules

Ignore case i Dot matches newlines s

THE OUTPUT 🔎

Understand the pattern

JAVASCRIPT REGEXPReady

Select a recipe or write a rule

Unicode mode always on

How it was built

RULE → FRAGMENT

Each rule will appear here with its generated fragment and meaning.

THE PROOF 🧪

Check the edge cases

Match mode

Mark what should match. The workshop shows where the pattern agrees or surprises you. Up to 100 examples; 2,048 UTF-16 code units per string. Longer input is kept but cannot be tested.

Choose a recipe to load example strings.

Write the rule.Read the regex.

Write your rules

Understand the pattern

How it was built

Check the edge cases

Write the rule.
Read the regex.