Regex API — IteraTools

About this tool

Test and extract data using regular expressions. Supports four modes: test (boolean match), match (first match with groups), matchAll (all matches up to 1000), and replace (find and replace). Full support for named capture groups, all JavaScript regex flags (g, i, m, s, u, y). Runs entirely locally — no external API calls.

Quick Start — Find All Matches

curl -X POST https://api.iteratools.com/text/regex \
  -H "Authorization: Bearer YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "pattern": "(?P<year>\\d{4})-(?P<month>\\d{2})-(?P<day>\\d{2})",
    "text": "Events on 2026-03-29 and 2026-04-15",
    "mode": "matchAll"
  }'

Response (matchAll)

{
  "ok": true,
  "data": {
    "mode": "matchAll",
    "pattern": "(?<year>\\d{4})-(?<month>\\d{2})-(?<day>\\d{2})",
    "flags": "g",
    "matches": [
      {
        "match": "2026-03-29",
        "index": 10,
        "groups": ["2026", "03", "29"],
        "namedGroups": { "year": "2026", "month": "03", "day": "29" }
      },
      {
        "match": "2026-04-15",
        "index": 25,
        "groups": ["2026", "04", "15"],
        "namedGroups": { "year": "2026", "month": "04", "day": "15" }
      }
    ],
    "count": 2
  }
}

Test Mode Example

curl -X POST https://api.iteratools.com/text/regex \
  -H "Authorization: Bearer YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{"pattern": "^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\\.[a-zA-Z]{2,}$", "text": "user@example.com", "mode": "test"}'

{ "ok": true, "data": { "mode": "test", "pattern": "...", "flags": "", "matches": true } }

Parameters

pattern (required) — Regex pattern (max 500 chars)
text (required) — Text to match against (max 100KB)
flags (optional) — Regex flags: g, i, m, s, u, y
mode (optional) — test, match, matchAll (default), or replace
replacement (required for replace mode) — Replacement string, supports $1, $<name> backreferences

Modes

test — Returns { matches: true/false }. Quick boolean check.
match — Returns first match with index, groups, and named groups.
matchAll — Returns all matches (up to 1000) with groups. Auto-adds g flag.
replace — Find and replace. Returns result string, replacement count, and lengths.

Use Cases

Extract emails, URLs, phone numbers, dates from unstructured text
Validate input formats (emails, IPs, postal codes) in AI workflows
Parse log files and extract structured fields with named groups
Clean and transform text with regex replacements
Test regex patterns before embedding them in code
Extract data from HTML/XML snippets without a full parser

Pricing & Limits

$0.001 per request via x402 micropayment on Base (USDC)
Max text size: 100KB
Max pattern length: 500 chars
Max matches (matchAll): 1000
No external API calls — instant response

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