| Supported languages | Supported language of the Source code that is submitted in the Chainlink Functions request | Only JavaScript is supported for the moment. Your source code can only use vanilla Node.js features (you cannot import modules) |
| Maximum requests in flight | The maximum number of simultaneous Chainlink Functions requests that are not fulfilled yet by the DON | Limited by the effective balance |
| Maximum callback gas limit | The maximum amount of gas that you can set for Chainlink Functions to fulfill your callback function | 300,000 |
| Maximum subscriptions | Maximum subscriptions that you can create | unbounded |
| Maximum consumer contracts per subscription | The maximum number of consumer contracts that you can add to a subscription | 100 |
| Request fulfillment timeout | The maximum duration of an in-flight Chainlink Functions request. After this duration, the request times out, and your subscription won't be charged. The estimated request costs are locked, so you have to request that locked funds are returned to your subscription balance | 5 minutes |
| Maximum request size | The maximum size of a Chainlink Request. This includes the source code, arguments, and secrets | 30 kilobytes |
| Maximum returned value size | The maximum size of the value that your Function can return | 256 bytes |
| Maximum source code execution time | The maximum amount of time that a source code can run | 10 seconds |
| Maximum memory allocated to the source code | The maximum amount of memory allocated to your source code during execution | 128 megabytes |
| HTTP - Maximum queries | The maximum number of HTTP requests that your source code can make | 5 |
| HTTP - query timeout | The duration of an HTTP request before it times out | 3 seconds |
| HTTP - Maximum URL length | Length of the HTTP URL | 2048 characters |
| HTTP - Maximum request length | The maximum size of an HTTP request, including the request body and HTTP headers | 2 kilobytes |
| HTTP - Maximum response length | The maximum size of an HTTP response | 2 megabytes |