For developers & analysts

Energy prices and mortgage benchmarks in one clean API

Normalized supplier price lists across 5 markets (CZ, FR, UK, DE, IT) — electricity and gas, incl. the full daily Italian catalogue — plus official mortgage rate benchmarks (ČBA/ČNB, Bank of England, Bundesbank, ECB) and CZ savings account rates (bank rate sheets + ČNB ARAD averages). Refreshed automatically, append-only history, every data point with source and validity date. Market data only — never user data.

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Official data only — sourced from regulators, central banks and suppliers’ official price lists:

ERÚ · CRE · Ofgem · BNetzA · ČBA · ČNB · Bank of England · Deutsche Bundesbank · ECB

What you get

Energy price lists (5 markets)

Current approved supplier price lists for electricity and gas in Czechia, France, the UK, Germany and Italy (full daily catalogue from ARERA open data) — one unified schema. Our own normalized database built from official documents.

Mortgage rate benchmarks

Official average rates of actually agreed mortgages: ČBA Hypomonitor & ČNB (CZ), Bank of England quoted rates (UK), Bundesbank MFI statistics (DE), ECB MIR (FR). Monthly series with history back to 2000.

Provenance on every point

Each record carries its source URL and validity date. Regulator data comes under open licences (Licence Ouverte, OGL); attribution requirements pass through to you.

Weekly fresh, automatically

Pipelines run weekly with self-checks — invalid data is never written. History is append-only.

What you can build

Comparison widgets

Embed a live “cheapest offer vs. your tariff” widget in your fintech or real-estate app.

Rate dashboards

Track mortgage margins across 4 markets — one call gives you the whole monthly series for your BI tool.

Research & journalism

Cite verifiable numbers: every data point links to the official source document and its validity date.

Alerts & analysis

Poll weekly and diff price lists to detect supplier price changes before your users notice them.

Build a chart in 20 lines

Fetch the CZ mortgage benchmark history and render it with any chart library. Example with Chart.js:

const res = await fetch(
  "https://assetli.app/api/data/v1/mortgage-rates?market=CZ&history=true",
  { headers: { Authorization: "Bearer <key>" } }
);
const { series, attribution } = await res.json();
const cba = series.find(s => s.source === "cba-hypomonitor");

new Chart(document.getElementById("rates"), {
  type: "line",
  data: {
    labels: cba.history.map(p => p.month),
    datasets: [{
      label: cba.seriesName,
      data: cba.history.map(p => p.ratePct),
      borderColor: "#2563eb",
      fill: true, backgroundColor: "rgba(37,99,235,.08)",
    }],
  },
  options: { plugins: { subtitle: { display: true, text: attribution } } },
});

The result — average rate of actually agreed CZ mortgages (ČBA Hypomonitor):

2020202220242026

Zdroj / Source: ČBA Monitor, ČNB — data: Assetli

Or render a table

Energy price lists come as flat JSON records — map them straight into a table. Sample of GET /api/data/v1/energy-prices?market=GB:

supplier	productName	region	unit rate	standing charge	validFrom
Octopus Energy	Octopus 12M Fixed	london	24.8 p/kWh	44.5 p/day	2026-07-01
Ofgem	Energy price cap (default tariff)	london	26.35 p/kWh	44.78 p/day	2026-07-01
Octopus Energy	Octopus 12M Fixed	yorkshire	25.1 p/kWh	52.3 p/day	2026-07-01

Compare 4 markets in one view

One call per market gives you comparable official mortgage benchmarks — the same monthly schema for CZ, UK, DE and FR. Illustrative chart (the API returns the real values):

CZGBDEFR

Illustrative example

2020202220242026

Average rates of actually agreed mortgages across markets — illustrative shape of the real series. Zdroj / Source: ČBA, Bank of England, Deutsche Bundesbank, ECB — data: Assetli

Detect price changes (build your own events feed)

Every record carries a validity window (validFrom / validTo). Poll weekly, diff two responses, and you get a structured feed of supplier price changes — illustrative example:

supplier	productName	→ price (old)	→ price (new)	Δ	validFrom
Supplier A	Fix 24 (D02d)	1 890 CZK/MWh	1 790 CZK/MWh	−5,3 %	2026-06-01
Supplier B	Gas Standard (≤25 MWh)	1 540 CZK/MWh	1 590 CZK/MWh	+3,2 %	2026-06-15
Supplier C	Standard (no fix)	2 120 CZK/MWh	2 120 CZK/MWh	±0 %	—

Suppliers anonymised in this illustration; the API returns real supplier and product names.

API reference

Authentication: send your key as Authorization: Bearer <key> (or X-API-Key header). All endpoints are read-only GET, JSON responses, CORS enabled.

GET /api/data/v1/energy-prices

Current approved price lists. Parameters: market (CZ|FR|GB|DE|IT, default CZ), commodity (electricity|gas, default electricity).

curl -H "Authorization: Bearer <key>" \
  "https://assetli.app/api/data/v1/energy-prices?market=GB&commodity=electricity"

{
  "market": "GB",
  "commodity": "electricity",
  "count": 28,
  "asOf": "2026-07-03",
  "attribution": "Data: public supplier tariffs; reference: Ofgem price cap (OGL).",
  "data": [
    {
      "supplier": "Octopus Energy",
      "productName": "Octopus 12M Fixed",
      "commodity": "electricity",
      "tariffType": "single",
      "region": "london",
      "validFrom": "2026-07-01",
      "validTo": null,
      "sourceUrl": "https://api.octopus.energy/v1/products/...",
      "price": { "standingChargePencePerDay": 44.5, "unitRatePencePerKwh": 24.8 }
    }
  ]
}

GET /api/data/v1/mortgage-rates

Official mortgage rate benchmarks. Parameters: market (CZ|GB|DE|FR, default CZ), history=true for the full monthly series.

curl -H "Authorization: Bearer <key>" \
  "https://assetli.app/api/data/v1/mortgage-rates?market=CZ&history=true"

{
  "market": "CZ",
  "attribution": "Zdroj: ČBA Monitor (Česká bankovní asociace) a ČNB. ...",
  "series": [
    {
      "source": "cba-hypomonitor",
      "latest": { "month": "2026-05", "ratePct": 4.67 },
      "history": [ { "month": "2020-01", "ratePct": 2.36 }, "…" ]
    }
  ]
}

GET /api/data/v1/savings-rates

CZ savings account rates: market average of actually paid deposits (Zdroj: ČNB ARAD, monthly since 2002), CNB repo benchmark and current offers from official bank rate sheets (balance bands, conditions flag, provenance). history=true returns full monthly series.

curl -H "Authorization: Bearer <API_KEY>" \
  "https://assetli.app/api/data/v1/savings-rates?history=true"

{
  "market": "CZ",
  "attribution": "Zdroj: ČNB (dvoutýdenní repo sazba) a oficiální sazebníky bank. …",
  "benchmark": {
    "source": "cnb-repo-2t",
    "latest": { "month": "2026-07", "ratePct": 3.75 },
    "history": [ { "month": "1995-12", "ratePct": 11.3 }, "…" ]
  },
  "offersCount": 58,
  "offers": [{
    "bank": "Banka CREDITAS", "productName": "Spořící účet TOP (CZK)",
    "ratePct": 3.0, "conditional": false,
    "bands": [ { "fromAmount": 0, "toAmount": 500000, "ratePct": 3.0 }, "…" ],
    "validFrom": "2026-07-01", "validTo": null, "sourceUrl": "…"
  }, "…"]
}

Response fields

Both endpoints return JSON with an attribution string you must display. Key fields:

market, commodity	Requested market (CZ\|FR\|GB\|DE) and commodity (electricity\|gas)
data[].supplier / productName	Supplier and product as published in the official price list
data[].price	Market-specific price object (e.g. unit rate + standing charge; abonnement + kWh; Grundpreis + Arbeitspreis)
data[].validFrom / validTo	Validity window; validTo null = currently valid
data[].sourceUrl	Link to the official source document (provenance)
series[].latest / history	Mortgage benchmarks: latest month + optional full monthly series
attribution	Source attribution string — must be displayed with the data

One plan. Everything included.

€49/ month

7-day free trial — full access, no card required.

5 energy markets (incl. full IT catalogue), mortgage benchmarks + CZ savings rates
Full history (mortgages back to 2000)
10,000 requests/day
Source attribution & provenance on every record
Weekly refreshed, self-checked pipelines

How to start: email us and we'll issue your trial key within 24 hours. No self-service signup yet — you get a human instead.

Start 7-day free trial →

Get your key at info@assetli.app

Market data only — never user data. Sources retain their rights; attribution requirements apply (the attribution field must be displayed with the data). Data is provided as-is for informational purposes. Redistribution of the raw database requires a separate licence.

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