Test, Highlight & Extract Regular Expression Matches in Real Time

Q: What do the g, i, and m regex flags mean?

The "g" (global) flag finds all matches rather than stopping after the first; "i" makes matching case-insensitive; "m" (multiline) makes ^ and $ match the start and end of each line.

Q: How do numbered capture groups work?

Wrapping part of a regex in parentheses (...) creates a numbered capture group ($1, $2, etc.) that isolates specific substrings like an invoice ID or price from a larger match.

Inspect every regex match, named or numbered capture group, character index, and execution time with one-click pattern presets.

✓ Real-Time AST Match Table Target Keyword: "regex tester online javascript" (135,000/mo) Est. Ad RPM: $16 – $25

INPUT SOURCE 332 chars

Order Batch #402 — Processed 2026-10-17:
1. INV-8821-US  $149.00 — Annual Cloud Storage Plan (support@acme.io)
2. INV-8822-EU  $2450.50 — Enterprise Security Seat License (https://security.example.com/status)
3. INV-8823-APAC $89.99 — Edge CDN Bandwidth Add-on from node 192.168.42.18
4. Note: Pending manual review for draft #8824.

LIVE PROCESSED OUTPUT UTF-8 • CLIENT-SIDE

Processing...

Ready • 100% local execution Server Cost: $0.00 • Latency: <5ms

How to Use the Regex Tester & Debugger

STEP 01

Enter your regular expression pattern and flags (such as g, i, m) or choose a common preset from the toolbar.
STEP 02

Paste your test corpus into the input pane to see all matches extracted.
STEP 03

Review the Capture Groups table below or export all matches as structured text.

Frequently Asked Questions (Regex Tester & Debugger)

What do the g, i, and m regex flags mean?

The "g" (global) flag finds all matches rather than stopping after the first; "i" makes matching case-insensitive; "m" (multiline) makes ^ and $ match the start and end of each line.

How do numbered capture groups work?

Wrapping part of a regex in parentheses (...) creates a numbered capture group ($1, $2, etc.) that isolates specific substrings like an invoice ID or price from a larger match.