Free gas price API

Live gas prices for Ethereum and six other EVM chains, Bitcoin fee rates and the USD cost of common transactions. Free, no key, CORS enabled.

Base URL: https://mddqwppgucgzefzddajy.supabase.co/functions/v1/gas-api

Gas price for an EVM chain

GET https://mddqwppgucgzefzddajy.supabase.co/functions/v1/gas-api/v1/gas?chain=ethereum
   (chain = ethereum | base | arbitrum | optimism | polygon | bnb | avalanche, or chainid=8453)

{
  "chain": "ethereum", "chainId": 1, "unit": "gwei", "block": 26165984,
  "baseFee": 0.0662, "nextBaseFee": 0.0660,
  "priorityFee": { "slow": 0.001, "standard": 0.0023, "fast": 0.1129, "instant": 0.9 },
  "gasPrice":    { "slow": 0.0670, "standard": 0.0683, "fast": 0.1790, "instant": 0.966 },
  "timestamp": "2026-10-11T01:41:21.756Z"
}

Bitcoin fee rates

GET https://mddqwppgucgzefzddajy.supabase.co/functions/v1/gas-api/v1/bitcoin   →   { "unit": "sat/vB", "fastest": 2, "halfHour": 1, "hour": 1, "economy": 1, "minimum": 1 }

Cost to move crypto (USD, 12 networks)

GET https://mddqwppgucgzefzddajy.supabase.co/functions/v1/gas-api/v1/fees   →   { "unit": "USD", "networks": [ { "network": "tron", "cost_native": 0.089, "cost_stable": 2.24, "cost_stable_new": 4.42, ... } ] }

Drop-in replacements

• Blocknative-compatible

  /gasprices/blockprices and /chains, same JSON shape.

• gasnow.org-compatible

  /api/v3/gas/price in wei, like the original GasNow API.

• Etherscan gas oracle shape

  /api?module=gastracker&action=gasoracle

• ChatGPT, Claude and Cursor (MCP)

  The same data as tools for AI assistants, plus an OpenAPI spec.

Rate limits and fair use

Up to 30 requests per minute per IP, free. Over that the API answers 429 {"msg":"Too Many Requests"} with a Retry-After header; every response carries X-RateLimit-Limit and X-RateLimit-Remaining. Data changes every few seconds at most, so cache responses for at least 10 seconds and credit GasNow where the numbers are shown. Need more? Get in touch.