Synergic APIsSynergic APIs

API documentation

US Natural Gas Storage API

Since 2010

The Thursday release that moves gas markets: working gas in underground storage (BCF), for the Lower 48 and every EIA region, weekly since January 2010.

500 req/mo · No credit card required · One key, every API on the platform

  • Checking status…
  • Weekly since Jan 2010
  • 8 regions, aligned series
  • Unit: BCF
  • Release: Thursdays 10:30 ET (EIA-912)

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.

MethodPathSummary
GET/gas-storage/latest Free+Latest working gas levels for every region
GET/gas-storage/{region} Free+Latest working gas level for a single region
GET/gas-storage/{region}/history Free+Paginated storage history for a region

{region}: lower48 | east | midwest | south-central | salt | nonsalt | mountain | pacific. History: start/end (YYYY-MM-DD, keyset via meta.next_end), limit 1–100 (default 30).

Sample — 200 /gas-storage/latest

{
  "data": [
    { "region": "lower48", "period": "2026-07-10", "stock": 3024, "unit": "BCF", "source": "EIA" },
    { "region": "east", "period": "2026-07-10", "stock": 614, "unit": "BCF", "source": "EIA" }
  ],
  "meta": { "source": "U.S. Energy Information Administration" }
}
Get a free API key 500 req/mo · No credit card required

Errors, auth & limits

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

StatusCodeWhen
401UNAUTHORIZEDMissing X-Api-Key header, or invalid/revoked key.
400VALIDATION_ERRORBad query/path parameters.
404REGION_NOT_FOUND · NO_DATA · NOT_FOUNDUnknown value for the path parameter (the message lists the valid ones), no data for the requested range yet, or unknown route.
429RATE_LIMITEDPer-minute limit of your plan exceeded — check Retry-After.
429QUOTA_EXCEEDEDMonthly cap reached. Nothing is billed on top — resets on the 1st (UTC).
502UPSTREAM_ERRORThe origin API was unreachable — retry shortly.

Data provenance

The EIA Weekly Natural Gas Storage Report (form EIA-912), official survey data. The five regions sum to lower48 within ±1 BCF (official rounding); salt + nonsalt make up south-central. Published Thursdays 10:30 ET on the prior Friday week — the latest point is typically 6–13 days old. 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-storage/latest

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.