A URL inspection API for developers and SEO teams

Trace a URL. See every hop,
every header, one response.

Checkredirects.io is a URL inspection API for developers and SEO teams. Trace the full redirect chain, catch the 404 that only Googlebot sees, audit the cert that expires next month, batch up to 500 URLs, and send results back into Google Sheets with your passthrough columns intact. One Go engine sits behind the REST API, web app, and MCP server.

live trace · /v1/inspect

try one:

code

url

time

protocol

paste a URL above and press Trace to see its chain

02 · ONE PRODUCT

One engine. Six surfaces.

No developer plan and no SEO plan. One product, one engine, one set of docs. The REST API, web UI, MCP server, Sheets export, GitHub Action, and no-code hubs all hit the same endpoints and return the same verdict shapes.

POST /v1/inspect REST API curl, fetch, or the client of your choice. 50+ endpoints, OpenAPI spec, signed webhooks with delivery tracking. Best when: wiring into CI, dashboards, internal tools app.checkredirects.io Web app Paste a list, watch the chain build live, hand the read-only link to a client. No API key, no command line. Best when: weekly audits, client handoffs, ad-hoc QA mcp://checkredirects MCP server Plug into Claude, Cursor, or any MCP-aware client. Let the assistant audit a sitemap and write the summary. Best when: "summarize what changed" beats opening a tab sheets.google.com Google Sheets Auto-write results into the sheet you already share with the team. Your passthrough columns ride along intact. Best when: the audit needs to live next to the campaign data actions/checkredirects GitHub Action Run a batch against your critical URLs on every PR. Fail the build if anything 4xx'd. Comment the diff on the PR. Best when: redirects are part of the deploy contract zapier · n8n · make No-code hubs Trigger checks from a form, a Slack command, a scheduled flow. Fan results out to whatever you already use. Best when: you live somewhere else and need this to show up there

all six clients hit the same Go engine · same endpoints · same response schema

03 · WHAT IT DOES

Capabilities by endpoint.

Every feature is a /v1/* call. The web app, MCP server, GitHub Action, and Zapier connector are clients of the same API. No UI-only features.

POST /v1/inspect

Trace a single URL, end to end.

Follow the full chain. Capture every hop's status, headers, TLS certificate, IP, protocol, and DNS/TCP/TLS/TTFB timing in one response. No follow-up calls for the common fields.

CORE

POST /v1/batch

Up to 500 URLs, async, with webhooks.

Submit a sitemap, a CSV, or a JSON list. Attach passthrough metadata. Get a signed webhook on completion, or poll the progress endpoint. No held connections, no timeouts. Sheets export available on completion.

CORE

POST /v1/monitors

Scheduled checks with change detection.

Run an inspection every N minutes. Get notified the moment the chain changes: a new hop, a different status, a cert about to expire. Backed by a deterministic diff, not a hash of the page.

PRO+

POST /v1/agents/compare

Same URL, 38 agents, one call.

Googlebot, GPTBot, iPhone Safari, your custom UA. See exactly where responses diverge. Catches cloaking, geo-rewrites, and the 404 that only one specific bot ever sees.

PRO+

mcp://checkredirects

MCP server for AI assistants.

Drop into Claude Desktop, Cursor, or any MCP-aware client. Let the assistant audit a sitemap and write you the summary in plain language. No copy-pasting between tools.

NEW

POST /v1/exports

Sheets, CSV, and passthrough.

Auto-write results to a Google Sheet. Download CSV with your input columns preserved. Every result gets a shareable, read-only link the client can open without an account.

EXPORT

04 · API EXAMPLE

A real /v1/inspect response.

Abridged. Hops, timing, TLS, security headers, and page metadata are all included by default. One round-trip per question.

POST /v1/inspect 200 OK · 184ms

curl -X POST https://api.checkredirects.io/v1/inspect \
  -H "Authorization: Bearer httpnd_••••" \
  -H "Content-Type: application/json" \
  -d '{
    "url": "https://t.co/abc123",
    "agent": "googlebot",
    "include_tls": true,
    "include_security_headers": true
  }'

# ↓ response
{
  "url": "https://t.co/abc123",
  "final_status": 200,
  "final_url": "https://example.com/landing",
  "total_time_ms": 470,
  "hop_count": 4,
  "chain": [
    { "status": 301, "url": "https://t.co/abc123", "time_ms": 84 },
    { "status": 301, "url": "https://bit.ly/3K9pQrz", "time_ms": 112 },
    { "status": 302, "url": "https://example.com/r?utm=tw", "time_ms": 96 },
    { "status": 200, "url": "https://example.com/landing", "time_ms": 178 }
  ],
  "tls": { "valid": true, "issuer": "Let's Encrypt R3", "expires_in_days": 91 },
  "security_headers": { "hsts": true, "csp": false, "xfo": "SAMEORIGIN" },
  "verdict": "healthy_long_chain"
}

Verdict, not just status.

Every response carries a named verdict (healthy, loop, broken, insecure, or cert_expiring), so you branch on it without writing the heuristic yourself.

Passthrough metadata.

Attach tag, campaign_id, anything. Comes back on every result and in your CSV. Built for joining audits to your own data.

Webhooks with delivery state.

Batches POST you a signed JSON on completion. The response tells you whether the webhook landed.

HTTPS-only is opt-in.

When HTTPS refuses or times out, we retry on HTTP and tell you. Set https_only: true for strict.

05 · PRICING

Three plans. Free includes 250 checks/month.

The free tier includes the full API, the MCP server, and shareable links. No card required. Upgrade for volume, monitoring, webhooks, or team seats.

Free

$0/mo

For occasional checks and weekend audits.

monthly checks250

batch size25 URLs

api rate10 / sec

mcp serveryes

sheets exportyes

shareable linksyes

monitorsnone

agent comparenone

webhooksnone

team seatsnone

Start free →

Pro

$8/mo

For SEO teams running real migrations.

monthly checks15,000

batch size200 URLs

api rate25 / sec

monitors50

agent compareyes

agent packsyes

webhooksyes

sheets auto-exportyes

saved presetsyes

team seatsyes

Start Pro →

Business

$25/mo

For agencies, in-house platforms, and teams.

monthly checks100,000

batch size500 URLs

api rate50 / sec

monitors250

agent compareyes

webhooksyes

sheets auto-exportyes

team seatsyes

audit logyes

priority supportyes

SSOon request

Start Business →

06 · ENDPOINT CATALOG

Twelve of 50+ endpoints.

A sampling. Full reference at /docs.

POST/v1/inspectTrace a single URL end-to-endcore POST/v1/batchAsync batch up to 500 URLscore GET/v1/batch/{id}/progressPoll batch progresscore GET/v1/batch/{id}/resultsStream results with passthroughcore POST/v1/monitorsCreate a recurring URL monitorpro+ POST/v1/monitors/{id}/pausePause without losing configpro+ POST/v1/agents/compareDiff 38 user agents on one URLpro+ GET/v1/agentsList available agents + packscore POST/v1/presetsSave a reusable inspection configpro+ POST/v1/exports/sheetsPush a result set into a Sheetcore GET/v1/usageCurrent month's check countercore POST/v1/api-keysMint a key, scoped or unscopedadmin

… and 38 more · view full OpenAPI spec →

Trace a URL. See every hop, every header, one response.