Optimism Etherscan · Rate Limits

Optimistic Etherscan Rate Limits

Rate limit definitions for the Optimism Etherscan API (OP Mainnet, chainid=10). Access is unified through Etherscan API V2 with per-tier limits enforced per API key across all chains. The free tier covers select chains at 3 calls/second; paid tiers scale from 5 to 30+ calls/second.

Optimistic Etherscan Rate Limits is the machine-readable rate-limit profile for Optimism Etherscan on the APIs.io network, conforming to the API Commons Rate Limits specification.

It captures 13 rate-limit definitions, across the free, lite, standard, advanced, and professional tiers, measuring requests_per_second and requests_per_day.

The profile also includes 6 backoff/retry policies defined and response codes documented for throttled, quotaExceeded, and serviceUnavailable.

Tagged areas include Blockchain, Optimism, Layer 2, Ethereum, and EVM.

13 Limits Throttle: 429 Quota: 429
BlockchainOptimismLayer 2EthereumEVMWeb3Rate LimitingQuotasThrottling

Limits

Free Tier Per-Second Rate api-key
requests_per_second · second
3
Free Tier Daily Quota api-key
requests_per_day · day
100000
Lite Tier Per-Second Rate api-key
requests_per_second · second
5
Lite Tier Daily Quota api-key
requests_per_day · day
100000
Standard Tier Per-Second Rate api-key
requests_per_second · second
10
Standard Tier Daily Quota api-key
requests_per_day · day
200000
Advanced Tier Per-Second Rate api-key
requests_per_second · second
20
Advanced Tier Daily Quota api-key
requests_per_day · day
500000
Professional Tier Per-Second Rate api-key
requests_per_second · second
30
Professional Tier Daily Quota api-key
requests_per_day · day
1000000
Pro Plus Tier Per-Second Rate api-key
requests_per_second · second
30
Pro Plus Tier Daily Quota api-key
requests_per_day · day
1500000
Enterprise Negotiated Limit contract
requests_per_second · second
-1

Policies

Backoff Strategy
Clients should implement exponential backoff with jitter, honoring the Retry-After header when present after a 429 response.
Burst Handling
Short bursts above the steady-state limit are tolerated up to the documented burst ceiling before throttling engages.
Quota Reset
Daily quotas reset at midnight UTC. Per-second windows operate on a sliding basis.
Shared Key Scope
Rate limits are enforced per API key across all Etherscan V2 chains. Optimism (chainid=10) requests count against the same key quota as requests to other supported chains.
Fair Use
Even on uncapped enterprise tiers, sustained usage that materially impacts shared infrastructure may be subject to fair-use throttling.
Attribution
Free tier usage requires attribution noting the application is "Powered by Optimism Etherscan APIs" except for personal or private usage.