Limits - Blast API Documentation

The following page showcases all the limitations inside the Blast API.

Blast API Limits

1. RPS - Requests Per Second

Each Blast API plan comes with a limit of requests per second. The limit is per project meaning that it is shared for all endpoints created in that project.

The limit is implemented using a sliding window algorithm. For example, let's assume that we have a plan that comes with a limit of 5 requests per second and have the following distribution of requests in the first second (each segment represents 0.1 seconds).

Legend:
S - successful request
R - rate-limited request

| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
| S |   |   | S | S | S | S | R | R | R |
|<------------------------------------->|

At 0.7s, we start hitting the rate limit since we already made
5 requests this second.

| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 |
| S |   |   | S | S | S | S | R | R | R |   |   |
    |<------------------------------------->|

At 1.1s we have only 4 requests in the sliding window so we can
make another one.

| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 |
| S |   |   | S | S | S | S | R | R | R |   | S | R | S |
                |<------------------------------------->|

Since we made a request at 1.1s, we need to wait until 1.3s to make
another one.

info

Note: unless otherwise specified, request refers to this definition.

2. WebSocket Connections Limit

Each project you create in your Blast API plan has a limit of 1000 WebSocket connections (this is shared across all the endpoints in the project).

3. HTTP Body Limits

The Blast API enforces the following limits for HTTP requests made against its endpoints:

Name	Limit
HTTP Request Header	8 KB
HTTP Request Body	1 MB
HTTP Response Header	8 KB
HTTP Response Body	128 MB

4. WebSocket Message Limits

Name	Limit
Client -> Blast API WebSocket Message	1 MB
Blast API -> Client WebSocket Message	128 MB

5. Method-specific Limits

• eth_getLogs requests can have a block range of at most 500 on the Free plan and 2000 blocks on the Developer and Startup plans for all chains that support this method