Gas-price history percentiles API

Read eth_feeHistory over the last N blocks from a free public RPC and derive the base-fee distribution: p10/p50/p90 percentiles in gwei, min/max, the current level, and a send-or-wait recommendation based on where the current fee sits in the recent range. The value-add is the percentile derivation — chain/gas gives only the spot fee; this tells you whether now is cheap or expensive. Answers 'is gas cheap right now', 'gas price percentiles', 'should I wait to send', 'recent base-fee range'.

Price$0.01per request

MethodPOST

Route/v1/chain/gas-history

StatusLive

MIME typeapplication/json

Rate limit60/minute

Cache3600s public

chaingasfeepercentilefeehistoryevmbasefeegwei

API URLhttps://x402.hexl.dev/v1/chain/gas-history

Integration docs

Example request

{
  "chain": "ethereum",
  "blocks": 100
}

Example response

{
  "chain": "ethereum",
  "blocks": 100,
  "currentBaseFeeGwei": 12.4,
  "minGwei": 8.1,
  "p10Gwei": 9.3,
  "medianGwei": 14.7,
  "p90Gwei": 22.6,
  "maxGwei": 31.2,
  "level": "below-median",
  "recommendation": "Below the recent median — reasonable time to send."
}

Input schema

{
  "type": "object",
  "required": [],
  "properties": {
    "chain": {
      "type": "string",
      "enum": [
        "base",
        "ethereum"
      ],
      "default": "base",
      "examples": [
        "ethereum"
      ]
    },
    "blocks": {
      "type": "number",
      "default": 50,
      "examples": [
        100
      ]
    }
  }
}

Output schema

{
  "type": "object",
  "additionalProperties": true
}