US Retail Fuel Prices API

Base URL & authentication

All endpoints live under one base URL. Authenticate every request with your key in the X-Api-Key header — no OAuth, no signing. The same key works on every API of the platform.

# Base URL
{{GATEWAY_URL}}

# Every request
X-Api-Key: sk_live_YOUR_KEY

Missing or invalid keys return 401 — see errors. The demo endpoint is the only keyless route.

Endpoints

All paths relative to the base URL. Every 200 ships ETag, Cache-Control and RateLimit-* headers.

Sample — 200 /fuel/latest

{
  "data": [
    { "fuel": "diesel", "area": "us", "period": "2026-07-28", "price": 3.71, "unit": "USD per gallon", "source": "EIA" },
    { "fuel": "gasoline", "area": "us", "period": "2026-07-28", "price": 3.42, "unit": "USD per gallon", "source": "EIA" }
  ]
}

Errors, auth & limits

One uniform error contract everywhere: { "error": { "code", "message" } } with stable, machine-readable codes — shared by every API on the platform.

Data provenance

Example

curl -H "X-Api-Key: sk_live_YOUR_KEY" \
  https://api.synergicapis.com/fuel/latest

import requests

r = requests.get(
    "https://api.synergicapis.com/fuel/latest",
    headers={"X-Api-Key": "sk_live_YOUR_KEY"},
)
r.raise_for_status()
print(r.json()["data"])

const res = await fetch("https://api.synergicapis.com/fuel/latest", {
  headers: { "X-Api-Key": "sk_live_YOUR_KEY" },
});
const { data } = await res.json();
console.log(data);

Live demo

Real request against the production API — no key needed here (demo endpoint, 5 requests/minute).

Press the button to fetch the latest official figures.

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