eth_feeHistory

EIP-1559 fee history: base fee per gas and gas-used ratios for a range of recent blocks, plus optional reward percentiles (priority fees) per block. This is the standard input for fee estimation — wallets and SDKs use it to suggest maxFeePerGas and priority fee values instead of guessing from a single eth_gasPrice number.

Example request

curl -s https://rpc.swiftnodes.io/rpc/eth?key=YOUR_API_KEY \
  -X POST -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"eth_feeHistory","params":["0x14","latest",[25,50,75]]}'

Replace YOUR_API_KEY with your SwiftNodes key (free tier available).

Chain support — 51/54 chains

Auto-probed 2026-08-25 through the real customer path (auth, routing, failover). ✓ served · ± served by some upstreams of that chain · ✗ unavailable. Full matrix: method support.