| API | Per-Minute | Per-Day | Cost | Auth Type | Scope |
|---|---|---|---|---|---|
| GSC Search Analytics | 1,200 QPM/user, 1,200 QPM/site | 30M QPD/project | Free | Service Account | Per user + per site |
| GSC URL Inspection | 600 QPM/site | 2,000 QPD/site | Free | Service Account | Per site |
| GSC Sitemaps | Standard | Standard | Free | Service Account | Per site |
| PageSpeed Insights v5 | 240 QPM | 25,000 QPD | Free | API Key | Per project |
| CrUX API | 150 QPM (shared) | Unlimited | Free | API Key | Per project |
| CrUX History API | 150 QPM (shared with CrUX) | Unlimited | Free | API Key | Per project |
| Indexing API | 380 RPM total, 180 read/min | 200 publish/day | Free | Service Account | Per project |
| GA4 Data API | 10 concurrent | ~25K tokens/day | Free | Service Account | Per property/project |
| Knowledge Graph | -- | 100,000 QPD | Free | API Key | Per project |
| Custom Search | -- | 10,000 QPD max | 100 free, $5/1K | API Key | Per project |
| Web Risk | 6,000 QPM | 100K/month | Free tier | API Key | Per project |
Key distinction: "Per site" quotas are scoped to a specific GSC property. "Per project" quotas are shared across all properties in a GCP project. "Per user" quotas are per authenticated user (service account).
When receiving 429 or 5xx errors:
Attempt 1: wait 1 second
Attempt 2: wait 2 seconds
Attempt 3: wait 4 seconds
Attempt 4: wait 8 seconds
Attempt 5: wait 16 seconds
Max: give up after 5 retries
Add random jitter (0-500ms) to each wait to avoid thundering herd.
| Code | Meaning | Applies To | Action |
|---|---|---|---|
| 400 | Bad request | All | Check URL format, request body |
| 401 | Unauthorized | Service Account APIs | Refresh credentials |
| 403 | Forbidden | GSC, GA4, Indexing | Check permissions (service account access) |
| 404 | Not found | CrUX, GSC | Insufficient traffic (CrUX) or invalid property (GSC) |
| 429 | Rate limited | All | Backoff and retry. Check Retry-After header. |
| 500 | Server error | All | Retry with backoff |
| 503 | Service unavailable | All | Retry with backoff |
Some Google APIs return a Retry-After header with 429 responses. When present, use this value (in seconds) instead of exponential backoff.
GA4 uses a token system rather than simple request counts:
- Simple 1-dimension, 1-metric report: ~1-5 tokens
- Complex multi-dimension, multi-metric: ~10-100 tokens
- Set returnPropertyQuota: true to monitor consumption
- Daily limit: 25,000 tokens per property per project
- Hourly limit: 5,000 tokens per property per project
- Concurrent: max 10 simultaneous requests
The CrUX API and CrUX History API share the same 150 QPM quota per project. Plan accordingly if querying both APIs in the same workflow.
All APIs used by seo-google are free at normal usage levels. No billing is required for: - PSI, CrUX, CrUX History (API key, unlimited free) - GSC (service account, 30M QPD) - Indexing API (service account, 200 publish/day) - GA4 Data API (service account, 25K tokens/day) - Knowledge Graph (API key, 100K QPD)
Only Custom Search and Web Risk have paid tiers at high volumes.