Requests & Limits

API variables and info

PER INSTANCE API WILL BE DEPRECATED JULY 1.
The Blockscout PRO API is a multichain API with enhanced limits based on your plan (5 rps included in the free plan). Check our PRO API docs for more info. Note that per-instance API access will be deprecated soon.

Type of API key	Rate limit value, req/sec	API key is defined by env variable (if applicable)	Rate limit for the API key managed by env variable	Description
No API key (by IP)	3 (old per-instance value)		API_RATE_LIMIT_BY_IP & API_RATE_LIMIT_BY_IP_TIME_INTERVAL	The default rate limit is 3 requests per minute. This limit applies to all requests that are not from whitelisted addresses and do not use an API key.
Temp token	3		API_RATE_LIMIT_UI_V2_WITH_TOKEN & API_RATE_LIMIT_UI_V2_WITH_TOKEN_TIME_INTERVAL	When frontend user reaches the default IP limit, they must solve a captcha to obtain a temporary token. This token provides a personal (not per-IP) rate limit of 5 req/sec. Token TTL is configured via API_RATE_LIMIT_UI_V2_TOKEN_TTL
Individual API key	10		API_RATE_LIMIT_BY_ACCOUNT_API_KEY_TIME_INTERVAL	An API key can be created by the user in the My Account section
Rate limit, if IP is whitelisted	25	API_RATE_LIMIT_WHITELISTED_IPS	API_RATE_LIMIT_BY_WHITELISTED_IP & API_RATE_LIMIT_BY_WHITELISTED_IP_TIME_INTERVAL	Rate limit for requests from whitelisted IPs
Per explorer instance API key	10	API_RATE_LIMIT_STATIC_API_KEY	API_RATE_LIMIT_BY_KEY & API_RATE_LIMIT_BY_KEY_TIME_INTERVAL	A per-instance API key (this feature was created before individual API keys existed and may have limited utility)
No rate limit API key	♾️	API_NO_RATE_LIMIT_API_KEY		Administrator API key

The default rate limit config of each API endpoint is described in the codebase and can be re-defined via API_RATE_LIMIT_CONFIG_URL env variable. Here you can find details on the rate limits config.

Some of the API endpoints have their own rate limit before showing captcha to the user:

API endpoint	Number of requests per period	Period
api/v2/key	♾️
api/v2/import/token-info	♾️
api/v2/import/smart-contracts/:param	♾️
api/account/v2/authenticate_via_wallet	1	1 hour
api/account/v2/send_otp	1	1 hour
api/v2/tokens/:param/instances/:param/refetch-metadata	50	1 hour
api/v2/advanced-filters/csv	50	1 hour
api/v2/tokens/:param/holders/csv	50	1 hour
api/v2/addresses/:param/transactions/csv	50	1 hour
api/v2/addresses/:param/token-transfers/csv	50	1 hour
api/v2/addresses/:param/internal-transactions/csv	50	1 hour
api/v2/addresses/:param/logs/csv	50	1 hour
api/v2/addresses/:param/election-rewards/csv	50	1 hour
api/v2/smart-contracts/:param/audit-reports	50	1 hour
api/health/*	5	1 second