Operations and limits

Public MegaETH JSON-RPC rate limits, payload limits, method caps, caching behavior, and WebSocket limits.

This page describes limits applied by the public MegaETH gateway. Method pages define the underlying request and response contracts.

HTTP request and response limits

Limit	Value
Default request body	128 KiB
Transaction-submission request body	2.5 MiB
Simulation and large-read request body	1.5 MiB
Batch size	100 requests
Batch subrequest budget	950
Response size	50 MiB

The 2.5 MiB body limit applies to eth_sendRawTransaction, eth_sendRawTransactionSync, and realtime_sendRawTransaction. The 1.5 MiB body limit applies to eth_call, eth_callMany, eth_createAccessList, and eth_estimateGas. A body that exceeds its limit is rejected with HTTP 413 and JSON-RPC code -32099.

The batch subrequest budget counts expanded work rather than only top-level batch items. For example, the calls inside eth_callMany contribute to that budget.

Method-specific limits

Method	Public gateway behavior
eth_call	Compute gas is capped at 60,000,000.
eth_callMany	At most 100 bundles and 100 total calls, 60,000,000 compute gas per call, and a 25-second timeout.
eth_estimateGas	The node applies a CPU-time limit whose current default is 0.5 seconds.
eth_feeHistory	blockCount is capped at 256.
eth_getLogs	The public indexed path does not impose a gateway block-range cap, but backend row, execution-time, memory, and response-size limits still apply.

Use bounded ranges and pagination for log scans and historical backfills. Do not assume that removing a block-range cap makes an unbounded query safe.

Read rate limits

Read requests are limited per client IP in fixed 10-second windows.

Category	Requests per 10 seconds	Typical methods
Instant	2,000	eth_chainId, eth_blockNumber, net_version, eth_accounts, web3_clientVersion, eth_getBalance, eth_getStorageAt
Simple	500	Basic block and transaction reads not assigned to another category
Compute	200	eth_call, eth_callMany, eth_estimateGas, eth_createAccessList, and debug trace methods
IO-heavy	200	eth_getLogs and eth_getBlockReceipts

Transaction-submission methods are exempt from these read limits. eth_callMany is charged by its inner calls rather than as one unit. A rate-limited request returns HTTP 429 with JSON-RPC code -32005.

Use exponential backoff with jitter for retryable throttling. Reduce concurrency and query size before increasing retry frequency.

Gateway caching

The public gateway has several internal caches. Their eligibility and lifetime depend on the method and selector: immutable block numbers and hashes can use longer-lived entries, while head-following reads use shorter policies or bypass a cache layer. See each method's reference page for its method-specific behavior.

The gateway's Workers read-cache layer is limited to:

• eth_getBlockByNumber
• eth_getBlockReceipts
• eth_getHeaderByNumber
• web3_clientVersion

For the block-selecting methods in this layer, only an explicit historical block number, a block hash, or earliest is eligible. The latest, pending, safe, and finalized tags bypass this layer. Other gateway cache layers can still apply method-specific short-lived policies to head-following reads.

Rate-limit accounting differs by request shape:

• A single read is rate-limited before cache lookup, so a cache hit consumes its category budget.
• A read batch checks the cache first and charges only cache misses against the read-rate budget.

Every public response includes Cache-Control: no-store for downstream caches. This header does not disable the gateway's internal cache. For methods eligible for the Workers read-cache layer, X-Workers-Cache-Status indicates whether that layer returned the response.

The gateway does not expose a request header or parameter that bypasses its internal cache.

WebSocket limits

Limit	Value
Connections per IP	5
Subscriptions per connection	5
Client message rate	5 messages per second per connection
Idle timeout	60 seconds
Maximum message size	64 KiB
Addresses in a logs filter	20
Topic positions in a logs filter	4

Use wss://mainnet.megaeth.com/ws for Mainnet and wss://carrot.megaeth.com/ws for Testnet. Send a lightweight request such as eth_chainId at least every 30 seconds to prevent idle disconnection. Reconnect, recreate subscriptions, and reconcile any missed data after a disconnect because notifications are not replayed automatically.

The public WebSocket endpoint accepts:

• eth_subscribe
• eth_unsubscribe
• eth_sendRawTransaction
• eth_sendRawTransactionSync
• realtime_sendRawTransaction
• eth_chainId

Related pages

• Error reference
• eth_subscribe
• eth_getLogs