API reference, Chain & reference

Block

  • Elysium: One Elysium block and every transaction in it: who called what, swaps, gas and fees.
  • HyperEVM: One HyperEVM block and every transaction in it: who called what, swaps, gas and fees.
  • Not on HyperCore: HyperCore blocks are its exchange state, not EVM transactions: an account's actions are in POST /info and on the wallet page

GET https://api.femtos.xyz/v1/blocks/{number}

Parameters

ParamInExample or valuesMeaning
numberpath23000 (Elysium); 49699586 (HyperEVM)Block number, or latest
layerqueryelysium (Elysium); hyperevm (HyperEVM)EVM layer

Example

Elysium

curl -H "Authorization: Bearer $FEMTOS_KEY" "https://api.femtos.xyz/v1/blocks/23000?layer=elysium"

HyperEVM

curl -H "Authorization: Bearer $FEMTOS_KEY" "https://api.femtos.xyz/v1/blocks/49699586?layer=hyperevm"

Key: Authorization: Bearer $FEMTOS_KEY. Get a free key, or with no browser through agent onboarding.

Response fields

FieldTypeMeaning
numberintBlock number
hashstring | nullBlock hash
timemsBlock time (the chain gives seconds)
kindsmall | big | blocksmall / big: HyperEVM's two block kinds, each with its own base fee and mempool (small: 3M gas, about one a second; big: 30M gas, about one a minute; a gas limit above 10M is big); block: Elysium's one kind
baseFeedecimalBase fee per gas, wei
tipP50decimal | nullMedian tip of its transactions, wei; null while unknown (tips of the history are read from the node after a restart)
burntdecimalBase fee × gas used, HYPE (exact)
feesdecimal | nullFees paid by its transactions, HYPE (exact); null when the node gave no receipts
txCountintTransactions in the block
transactions[]objectIn block order: {hash, index, type, from, fromEntity, to, toEntity, contractCreated, value, methodId, method, status, …}
transactions[].methodstring | nullThe function's name when known (the signatures most used on the layer)
transactions[].swaps[]objectIts swaps, decoded (indexer): {side, base, quote, baseAddress, quoteAddress, pair, usd}
prevint | nullPrevious block
nextint | nullNext block; null at the head

Related: Chain & reference

  • Freshness GET /v1/status Elysium, HyperCore, HyperEVM
    Head and lag of each layer, measured now.
  • Freshness stream WS status Elysium, HyperCore, HyperEVM
    The GET /v1/status answer (head and lag of each layer, live feeds), pushed whole on subscribe and at most once a second when it changes.
  • Blocks stream WS elysium.blocks | hyperevm.blocks Elysium, HyperEVM
    Each new HyperEVM block header, small and big blocks, from our node.
  • Gas tracker GET /v1/gas Elysium, HyperEVM
    Every HyperEVM block's base fee, gas used and tips over 1h to 7d, with stats and the latest block.
  • Gas stream WS elysium.gas | hyperevm.gas Elysium, HyperEVM
    Each new HyperEVM block's base fee, gas used and tips, from our node; the history is GET /v1/gas.
  • Transaction GET /v1/tx/{hash} Elysium, HyperEVM
    One transaction: status, gas, decoded transfers, swaps and liquidity, bridge legs and journey.
  • Elysium RPC POST /v1/elysium/rpc Elysium
    Free public Elysium mainnet RPC by Femtos (chain 99901), no key, read only (no transaction sending), for wallets and dapps, not for indexing (use the Femtos API for history): per IP 5 requests a second and 60 a minute, batches of 5, eth_getLogs over 1,000 blocks at most, state of the last 128 blocks only.
  • Stream stats WS stats HyperCore
    Our HyperCore stream health, once a second.
  • Check your key GET /v1/whoami Elysium, HyperCore, HyperEVM
    Answers the name your key is registered under, its tier, billing state and the limits in force.
  • OpenAPI document GET /v1/openapi.json Elysium, HyperCore, HyperEVM
    The OpenAPI 3.1 contract of every REST call, public.

More

Agent guide (agents.md)llms.txtOpenAPIMCP serverGet an API keyChangelog