Static + Browser-Only

HTTP Regex Tester and Validator Online

Test regex rules against JSON online. Put regex rules JSON on the left, validate an HTTP payload on the right, and highlight invalid or missing fields directly in the browser.

This is useful for HTTP request review, header validation, and regex-based request checks without uploading data.

Rules

Regex rules JSON

Paste regex rules JSON on the left and an HTTP payload on the right.

Payload

Payload HTTP

Validated payload with field-level regex highlights will appear here

What Is It

What is an HTTP regex tester and validator?

This page validates raw HTTP requests and headers against a rules JSON object where each field contains a regex pattern. It helps teams test whether headers and body values match expected formats before sharing, debugging, or using that request elsewhere.

Use Cases

When should you validate HTTP requests with regex rules?

Check API fixtures before QA or release review
Validate form payload patterns like email, phone, and member IDs
Review headers and JSON body fields against internal standards
Highlight HTTP headers or body values that break expected regex rules

Features

What this HTTP regex validation tool can do

Use a JSON object of regex rules as the source of truth
Validate headers such as Authorization and body fields such as body.memberId
Highlight invalid and missing values in HTTP payloads
Run locally in the browser with no upload

FAQ

Common questions

How do I test a payload against regex rules?

Paste your regex rules JSON on the left, paste the matching payload format on the right, and run validation. Invalid or missing fields are highlighted in red inside the payload viewer.

Can I validate HTTP fields?

Yes. Nested objects are supported, so rules like customer.memberId and customer.email work when the request structure matches.

Does this work only for HTTP text?

Yes. This page is focused on HTTP validation. Other regex pages are available for XML, HTML, CSV / TSV, SQL, logs, plain text, and HTTP payloads.

Does this upload the rules or payload?

No. Validation runs locally in the browser and no rules JSON or payload content is uploaded during the workflow.

Why HTTP regex validation matters before sharing or testing requests

Teams often assume sample payloads are valid until a downstream system rejects them. An HTTP regex validator makes those formatting problems visible before a payload reaches QA, support, docs, vendors, or AI workflows.

This is useful for headers and body values such as bearer tokens, member IDs, and status values where format errors are easy to miss.

Teams often search for a free regex tester online when they need to validate field formats, check sample payloads, enforce naming rules, or catch invalid values before QA, release review, or external sharing. A browser-only regex validator is especially useful when payloads, logs, or request examples should stay local and should not be uploaded to a remote validator.

Examples

Example HTTP rules and payload

The rules JSON defines regex patterns, and the payload is raw HTTP text with invalid values highlighted.

Regex rules JSONValidation rules

{
  "email": "^[A-Z0-9._%+-]+@[A-Z0-9.-]+\\.[A-Z]{2,}$",
  "phone": "^\\d{3}-\\d{3}-\\d{4}$",
  "status": "^(active|pending|paused)$",
  "customer": {
    "memberId": "^mem_\\d{3,}$"
  }
}

Payload HTTPInvalid fields highlighted

{
  "email": "john@example.com",
  "phone": "2045550199",
  "status": "trial",
  "customer": {
    "memberId": "204"
  }
}