eth_getBlockTransactionCountByNumber

eth_getBlockTransactionCountByNumber returns how many transactions sit in a single Base block, identified by its height or by a tag like latest, safe, or finalized. Base is Coinbase's OP Stack optimistic rollup, settling to Ethereum L1 and paying gas in ETH, with its sequencer producing a block roughly every 2 seconds — so this counter is a fast-moving signal of throughput. Send the request to https://base.therpc.io/YOUR_API_KEY (chain ID 8453, hex 0x2105). The response is the transaction count of the chosen block, hex-encoded.

Use cases

• Track real-time congestion by polling the latest block's count each time Base seals one — bursts from consumer and social apps show up here first.
• Build a block-fullness time series to feed fee-estimation heuristics, since fuller blocks on the ~2s Base cadence push priority fees higher.
• Iterate over a range of heights to flag empty blocks (sequencer idle) or unusually dense blocks tied to events like Aerodrome or Uniswap activity spikes.

Parameters

Response

Example request

1curl https://base.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H "Content-Type: application/json" \
4  -d '{
5    "jsonrpc": "2.0",
6    "method": "eth_getBlockTransactionCountByNumber",
7    "params": ["latest"],
8    "id": 1
9  }'

Try it live in the Base playground.

Errors & troubleshooting

Common pitfalls

• The pending tag counts transactions the Base sequencer has queued for the next block; that figure can shift between two back-to-back calls, so do not treat it as final.
• The result is a hex string such as "0x4a" — run parseInt(value, 16) before doing any numeric comparison or charting.

Supported networks

• Mainnet — Chain ID: 8453
• Sepolia — Chain ID: 84532

See also

• eth_getBlockTransactionCountByHash
• eth_blockNumber
• eth_getBlockByNumber
• eth_getTransactionByBlockNumberAndIndex

1curl https://base.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H 'Content-Type: application/json' \
4  -d '{"jsonrpc":"2.0","id":1,"method":"eth_getBlockTransactionCountByNumber","params":[""]}'