Every chart on this site, as JSON or CSV, with the date on every row.
The same numbers the pages draw — nothing derived for the API, nothing withheld from the page. One key, one endpoint, and a column saying where each number came from.
What you get. Every series we publish, as JSON or CSV, at one endpoint. Each row carries the day it belongs to, the unit it is measured in, the source it came from by name, and the day we last looked — so a number lifted into your model can still be dated a year later. There are 13 lines today and 8 of them serve rows; the rest are sources whose own terms let us publish our numbers from them but not their lists, and the catalogue says which is which before you ask for one.
What it costs. A free key gives you 100 requests an hour and the last 90 days of history — the same window the CSV on any chart page gives away without a key at all. Paid keys lift the rate and open the whole record.
What we will never do. Sell you a forecast, a scraped table we have no right to resell, or a number without its date. When a source stops publishing, the series says so on its page and the API stops returning new rows — it does not quietly carry the last number forward.
What it costs
| Tier | Price | Rate | History |
|---|---|---|---|
| Free | Free | 100 requests an hour | the last 90 days |
| Standard | £49 a month | 1,000 requests an hour | the whole record |
| Premium | £199 a month | 10,000 requests an hour | the whole record |
One example
curl -H "Authorization: Bearer pk_live_your_key_here" \ "https://menfem.com/api/v1/data/series/power.fleet?from=2026-08-01"
{
"data": [
{
"date": "2026-09-12",
"series": "fleet",
"key": "mean",
"value": 93.1,
"unit": "%",
"source": "the NRC",
"asOf": "2026-09-13"
}
],
"meta": {
"id": "power.fleet",
"unit": "%",
"source": "the NRC",
"since": "2026-08-14",
"asOf": "2026-09-13",
"historyFloor": "2026-06-16",
"total": 30,
"hasNext": false,
"nextCursor": null
}
}GET /api/v1/data/series lists every line with its licence and whether its rows may be resold. Add ?format=csv to any row request for the same rows as a file, and follow meta.nextCursor for the next page.
Getting a key
Keys are made at /developers/keys. Signing in is the only gate — there is no application and no waiting list.
If your agent speaks MCP, it can read all of this without a key: the server is at /api/mcp/menfem, and getSeries reads the same rows this page describes.