API documentation
US Natural Gas Price API
Since 1997The Henry Hub spot price (USD per MMBtu), daily since 1997 with official weekly, monthly and annual aggregates — straight from the U.S. Energy Information Administration.
500 req/mo · No credit card required · One key, every API on the platform
- Checking status…
- Henry Hub daily since 1997
- Weekly · monthly · annual aggregates
- USD per MMBtu
- Source: U.S. EIA
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.
| Method | Path | Summary |
|---|---|---|
| GET | /gas/latest Free+ | Latest published price for every frequency, one call. |
| GET | /gas/{frequency} Free+ | Latest price for one frequency — daily | weekly | monthly | annual. |
| GET | /gas/{frequency}/history Free+ | Paginated history per frequency: start/end, limit 1–100, keyset via meta.next_end. |
Sample — 200 /gas/latest
{
"data": [
{ "frequency": "daily", "period": "2026-07-13", "price": 3.02, "currency": "USD", "unit": "MMBtu", "source": "EIA" },
{ "frequency": "monthly", "period": "2026-06", "price": 2.97, "currency": "USD", "unit": "MMBtu", "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.
| Status | Code | When |
|---|---|---|
| 401 | UNAUTHORIZED | Missing X-Api-Key header, or invalid/revoked key. |
| 400 | VALIDATION_ERROR | Bad query/path parameters. |
| 404 | FREQUENCY_NOT_FOUND · NO_DATA · NOT_FOUND | Unknown value for the path parameter (the message lists the valid ones), no data for the requested range yet, or unknown route. |
| 429 | RATE_LIMITED | Per-minute limit of your plan exceeded — check Retry-After. |
| 429 | QUOTA_EXCEEDED | Monthly cap reached. Nothing is billed on top — resets on the 1st (UTC). |
| 502 | UPSTREAM_ERROR | The origin API was unreachable — retry shortly. |
Data provenance
Henry Hub spot from the U.S. Energy Information Administration: the daily series since 1997, with the official weekly/monthly/annual averages of that series. Period format follows the frequency (YYYY-MM-DD daily, YYYY-MM monthly…). Published with a typical 1–6 day lag; never estimated. This product is not endorsed by or affiliated with the EIA.
Example
curl -H "X-Api-Key: sk_live_YOUR_KEY" \ https://api.synergicapis.com/gas/latest
import requests
r = requests.get(
"https://api.synergicapis.com/gas/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/gas/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.