EV charging Live
Your EMS calculates charging need — the API returns the cheapest hours in the next 7 days, not just until tomorrow.
Decision Windows
Forecast · Decision · Auditable · Austria
Electricity price forecast for EMS, grid & pro storage — 7 days ahead
Auditable pre- and post-auction quality for control and planning signals. EMS vendors, integrators and storage operators scale with Professional or OEM — technicians and makers start free with Community (Fair Use, full 7-day horizon).
Reliable signals for flexibility and load shifting — proven, not promised
For your home and your installations
Homeowner or installer — the same interface for battery, EV, smart home and client projects.
- EV, home battery and heat pump — one interface
- Loxone, Home Assistant, Python and more — with code samples
- Same offering for homeowners and installers
Home battery Live
Charge / discharge / hold signals — for ML hours the Decision API uses conservative P10/P90 bands (charge/discharge, <code>price_basis</code> field) plus Decision Windows for targeted grid charging or export slots.
Charge & discharge
Heat pump & boiler Live
Shift flexible heat to cheap hours — query the best slots in your week window via Decision Windows.
Cheapest hours
Smart home & JSON API Live
REST API and Decision Windows for any JSON-capable system — Loxone, Home Assistant, ioBroker, Python, Rust and many more. Code samples in 14 languages with step-by-step guides.
PV export Live
Most expensive hours in a window for maximum export revenue — <code>mode=expensive</code> in Decision Windows (full tier).
Electricians, installers & partners Live
Manage multiple sites — higher limits for professionals.
Partner portalLive spot prices
Real exchange prices for today and tomorrow, AI forecast up to six days ahead — interactive and hourly.
- Exchange price today and tomorrow — hourly
- AI forecast for the next six days
- Change day, hover bars — price and day-over-day comparison at a glance
The best hours of the week
This is how your system plans with us — EV, battery, heat pump. Try it live, the same logic your smart home will use via API later.
- 7-day forecast instead of only watching tomorrow
- See when power is cheap or expensive — and where savings are possible
- Pick a scenario or set your own window — the table shows the best hours
Computing planning windows …
| Day | Hour | Slot price model price | Savings (median · 48h market) | Action | Source |
|---|
Technical details (JSON)
Forecast — no guarantee. Decisions depend on tariff, consumption, and setup.
Full API access with your own key — try for free.
AI forecast with uncertainty band Live
Orange = point forecast (centre), blue band = P10–P90 — same values as the full API tier.
- P10 = conservative lower bound (10% of cases even cheaper), P90 = upper bound — useful for battery and EMS logic
- ML hours from day after tomorrow only (D+2…D+6); exchange prices for today & tomorrow have no band
- Live from production cache — not a demo mock-up
Detailed explanation (expand)
The blue band shows the price range our AI expects for upcoming ML hours (from day after tomorrow) — not just a single number:
- Point forecast (≈ P50)
- The most likely hour-by-hour prediction — orange line in the chart,
price_ct_kwhin the API. Matches the 50th percentile (P50): the midpoint of the expected range between P10 and P90. - P10 — conservative lower bound
- In about 10% of similar situations the price was even lower. For grid charging, the Decision API often uses P10 — cautious enough for cheap windows without being overly pessimistic.
- P90 — conservative upper bound
- In about 90% of cases the price was lower; in 10% it could be higher. For discharge / export we use P90 — you do not plan too optimistically on high-price hours.
Why it matters: On sunny days the point forecast at midday may still be too high while P10 is already near zero — for batteries, EVs and heat pumps the band is a more robust planning basis than a single value.
P10–P90 band
Point forecast
Four building blocks — one platform
Forecast API, planning signals, Decision Windows for EMS automation and the account portal — with electricity cost comparison and archive-backed proof, all over HTTPS with your personal API key.
- Forecast API — hourly up to 6 days ahead (exchange + AI)
- Decision API (hourly signals) and Decision Windows (cheapest hours, energy-based planning)
- Account portal: forecast chart, savings potential (48 h vs. 7-day planning) and API key
Forecast API Live
Hourly electricity price for Austria — from today through 6 days ahead.
- Exchange price today & tomorrow, AI from day after tomorrow
- Full tier: a price band showing the likely range — more robust than a single forecast number
- Basic preview: up to 48 h (today & tomorrow) · Community/Professional: 7 days with API key
GET https://api.spotpriceapi.com/v1/forecast
X-API-Key: your-key
Planning signals Live
Hourly guidance for your energy system: when to charge, wait or discharge — included in Community, Professional and OEM (not in the anonymous Basic preview).
- Simple hourly signals: charge, hold or discharge — ready for battery, wallbox and heat pump
- Uses the forecast price band (P10/P90) — not just the midpoint, especially on volatile days
- Separate guidance for consumption (charging, heating) and export (PV feed-in)
GET https://api.spotpriceapi.com/v1/decision
X-API-Key: your-key
Find cheap hours Live
Your EMS asks: which N hours are cheapest or priciest in a window you set — up to 7 days ahead. Ideal for grid charging, wallbox and export optimisation.
- Plan by hour count or energy: e.g. 6 charging hours in 48 h, or 50 kWh at 11 kW — the API calculates the slots
- Cheapest hours for charging and heating, priciest for export — consume vs. export role, with gap between sessions and daily cap
- Includes a savings hint vs. 48 h day-ahead-only planning — ready for Loxone, Home Assistant and Python
GET https://api.spotpriceapi.com/v1/decision/windows
?energy_kwh=20&max_power_kw=11&mode=cheapest&role=consume
Account portal Live
Forecast chart, API key, savings potential check and integration guides — in the browser; guest demo without login.
- 7-day forecast with chart & table
- Savings potential — electricity cost comparison (48 h vs. 7-day plan), kW/kWh scaling
- Code samples — 14 languages, step-by-step Decision Windows
Portal: forecast & savings potential
After registration you see the forecast as an interactive chart and can check in the archive lookback how much you save with 7-day vs. 48 h-only planning for your grid draw — transparent, without empty promises.
- Interactive forecast chart after registration
- Electricity cost comparison 48 h vs. 7 days with real archive lookback
- No empty promises — real lookbacks instead of marketing
Forecast Live
Hourly price as chart and table — up to 48 h / today & tomorrow (Basic preview) or 7 days (Community/Professional). Chart includes negative prices (dynamic Y-axis). With a short summary in the portal.
- Interactive 7-day chart
- Exchange price vs. AI forecast
- Times in Austria (Vienna)
Savings potential Live
How much do you save on grid draw with 7-day planning instead of day-ahead only (~48 h)? Archive-backed electricity cost comparison — scaled to annual grid draw and connection power (guest demo: 28 days).
- Hit rate: are the recommended charging hours correct in the lookback?
- Savings in euros from your kW and kWh settings — daily minimum or weekly flexible
- Fair comparison: same actual spot prices, same daily replan rhythm — only the planning horizon differs
Forecast and savings potential are available as a free demo without login — a free account unlocks all 7 days and full features.
Get started in three steps
From registration to connecting your smart home — with ready-made samples in the portal.
Register
Free Community account — forecast, Decision API and portal under Fair Use (1 key, 120 requests/day).
Get your API key
After email confirmation you receive your key in the dashboard.
Connect your system
Loxone, Home Assistant, Python or ioBroker — ready-made samples including Decision Windows (grid charging) in the portal.
Model & evidence — transparency instead of fair-weather metrics
We separate pre-auction ML, day-ahead clearing and actuals — and report bias with sign. Assess risk honestly and control EMS with guardrails, not marketing curves.
A · Transparency — D−1 ML ≠ D−1 DA
Pre-auction forecast (D−1 ML) measures true predictive skill before the auction. D−1 DA verifies post-clearing ingest — typically near 0 ct/kWh MAE when ingest is correct.
B · Guardrails — enterprise-grade inference
Multi-stage plausibility (incl. D−1/D−2) protects against bad incentives — without blanket-blocking genuine negative-price signals on summer weekends.
C · Improvement — auditable evolution
Raw archives and replays show how retraining and promotion gates sharpen quality.
No blanket savings guarantees. Metrics and archives exist for traceability.
Pricing — three clear paths
No B2C micropayments. Community for private labs and smart homes under Fair Use. Professional for commercial multi-site use. OEM for device makers and grid operators.
Fair Use · private
Community
Free
Full 7-day forecast + Decision Windows · 1 API key
- 120 requests / day (Fair Use for private smart home & lab)
- Private smart home / lab (HA, Loxone, ioBroker)
- No commercial redistribution · no multi-site
- Community support
B2B · Stripe
Professional
€99/mo
or €990/year excl. VAT · commercial use · up to 50 sites
- Full APIs including Decision Windows
- Partner portal (multi-key) · up to 50 sites
- High rate limits
- Audit exports / quality PDFs
- Priority support (target 24h business day)
Contract · Admin
OEM / Enterprise
On request
From about €490/month · white-label, volume, custom SLA
- Dedicated limits & key management
- Device / firmware embedding
- Grid & utilities
- 12-month contract, admin provisioning
Technicians try Community privately — companies license Professional or OEM.
Frequently asked questions
What is the difference between tomorrow's exchange price and a 7-day forecast?
Tomorrow's exchange price (day-ahead) usually covers today and tomorrow — about 48 hours of visibility. SpotpriceAPI adds an hourly AI forecast for the full week (today through 6 days ahead). That helps you spot cheap charging windows earlier — for EV, battery and heat pump. Under <a href="/fc-verification">Savings potential</a> you can see a fair electricity cost comparison: ~48 h only vs. full 7-day planning.
Does SpotpriceAPI work with Loxone?
Yes. Under <a href="/code-samples">Code samples</a> you find step-by-step guides for Loxone PicoC, Home Assistant, Python, curl and more — including Decision Windows for grid charging (14 languages).
Do I need a dynamic electricity tariff?
For real cost savings, yes — the API delivers spot price forecasts. With a fixed tariff you can still use the signals for load shifting and self-consumption.
Is the API only for Austria?
The focus is Austria (EPEX Spot AT). More countries are planned long term.
How secure is the API key?
Your personal key is sent only in the HTTP header — never in the URL.
What is Decision Windows?
GET /v1/decision/windows returns the N cheapest or most expensive hours in a window up to 7 days — e.g. via count=6 or energy_kwh=20&max_power_kw=11. Default: allocation=global (N cheapest hours in the window); optional day_first for day quotas. Available in Community (Fair Use) as well as Professional and OEM. Guides under Code samples.
What do P10, P90 and point forecast (P50) mean?
The blue band shows the price range our AI expects for upcoming ML hours (from day after tomorrow) — same values as in the live chart and API (price_p10_ct_kwh, price_p90_ct_kwh).
- Point forecast (≈ P50)
- The most likely hour-by-hour prediction — orange line in the chart,
price_ct_kwhin the API. Matches the 50th percentile (P50): the midpoint of the expected range between P10 and P90. - P10 — conservative lower bound
- In about 10% of similar situations the price was even lower. For grid charging, the Decision API often uses P10 (
price_basis: p10) — cautious enough for cheap windows. - P90 — conservative upper bound
- In about 90% of cases the price was lower; in 10% it could be higher. For discharge / export we use P90 (
price_basis: p90).
Why it matters: On sunny days the point forecast at midday may still be too high while P10 is already near zero — for batteries, EVs and heat pumps the band is a more robust planning basis than a single value.
Exchange prices (today & tomorrow) have no band — the market price is fixed there.
What does savings potential (/fc-verification) show?
Under Savings potential we compare in the archive lookback the electricity costs you would have incurred with day-ahead-only planning (~48 h visibility) vs. planning with the 7-day forecast — for your grid draw, connection power (kW) and selectable scenarios (battery, EV, heat pump, export).
You can choose daily minimum (at least every day) or weekly flexible (total kWh in 7 days spread across cheap days). Both sides use the same actual spot prices and daily replan at ~12:00 — only the planning horizon differs.
Available as a guest demo without login; hit rate and detailed breakdown after sign-in.
What is the difference between planning signals and Decision Windows?
Planning signals (/v1/decision) give an hourly recommendation: charge, hold or discharge — for continuous EMS rules with battery, wallbox or heat pump. Decision Windows (/v1/decision/windows) pick exactly the N cheapest or priciest hours in a window — default allocation=global (top-N in the window); optional day_first for day quotas. Both use the 7-day forecast; Windows are ideal for fixed charging slots and hourly EMS polling including replan after day-ahead.
From lab to company
Use Community for HA, Loxone and prototypes. When customer sites or OEM embedding are needed, move to Professional or talk to us about OEM.
Refer a friend
Recommend SpotpriceAPI.com by email or WhatsApp.
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