Fully offline
All property data is embedded, every calculation runs locally on the device. No dead zone stops you, no server can go down.
iOS · built for the machine room
Property data and calculators
Property data and calculators
that work without a network.
12 professional calculators, a formula library and 14 refrigerants – all embedded on your iPhone. Enter values, get a live result, done. No login, no tracking, no loading bar.
Coming soon to the App Store
See the features
Four languages with regional number formatting – offline.
Why this app
A tool for the field, not the office.
On the roof, in the machine room, at the customer's site, in training – wherever fast, reliable numbers are needed. Often without a stable network. That is exactly what it is built for.
No account
No sign-up, no registration, no login. Open the app, get going.
Privacy
No data collection, no tracking, no analytics SDKs, no ads.
Fast
Direct input, live result, large controls – usable even with gloves on.
Four languages
German, English, Spanish, French – with regional number formatting.
Precisely calculated
Property data from CoolProp, established engineering formulas. No rough rules of thumb, but interpolated saturation data.
How it works
Three steps to a result.
1
Pick a tool
Tap a calculator or refrigerant – everything is right at hand, no searching.
2
Enter values
Large fields, sensible units, a live result with every input.
3
Save or export
The result lands in your history and can be shared as a PDF with Pro.
The toolbox
12 professional calculators that really calculate.
Each calculator saves its result to the history and can be exported as a PDF with Pro. Four are free forever.
SuperheatFree
SubcoolingFree
Pressure → TemperatureFree
Unit converterFree
Cooling-load wizardPro
COP / coefficient of performancePro
log p–h diagramPro
Mass flowPro
Compressor volume flowPro
Pipe friction lossPro
Refrigerant chargePro
Cooling capacityPro
Free – no restrictions
Pro – one entitlement unlocks everything
What makes it special
Four things we are proud of.
Pressure ↔ temperature with PT diagram
Conversion along the saturation curve, with bubble and dew line for zeotropic blends and the working point plotted.
Complete cycle process
Real process with isentropic efficiency – COP for refrigeration and heat pump, shown in the log p–h diagram.
Guided cooling-load estimate
Step-by-step wizard with room-type presets, location-based solar estimate and an equipment recommendation.
Searchable formula library
Categorised by cycle process, flow, heat transfer and more – each with a legend of the formula symbols.
A look inside the app
Dark, tidy, usable with big fingers.
KälteToolbox Pro
Free to use. Pro when you need more.
The app is free with a solid free scope. Pro unlocks the professional tools, PDF export and unlimited history – one entitlement, everything open.
Monthly
€2.99 / month
Cancel anytime.
Popular
Yearly
€29.99 / year
Cheaper than 12 monthly payments.
Lifetime
€59.99 once
Buy once, keep it forever.
Purchases run through your Apple ID – without the app needing an account or server. Restore anytime; subscriptions are managed in your App Store settings.
Property-data library
14 refrigerants as data sheets.
With key figures and saturation data, fully offline: GWP (AR5), critical point, temperature glide, saturation pressures and the vapour-pressure curve.
| Refrigerant | Type | GWP (AR5) | Crit. temp. |
|---|---|---|---|
| R134a | Pure fluid | 1300 | 101.1 °C |
| R410A | Blend | 1924 | 71.3 °C |
| R32 | Pure fluid | 677 | 78.1 °C |
| R290 Propane | Pure fluid | 3 | 96.7 °C |
| R744 CO₂ | Pure fluid | 1 | 31.0 °C |
| R404A | Blend | 3943 | 72.1 °C |
| R407C | Blend | 1624 | 86.2 °C |
| R22 | Pure fluid | 1760 | 96.1 °C |
| R1234yf | Pure fluid | 1 | 94.7 °C |
| R1234ze(E) | Pure fluid | 1 | 109.4 °C |
| R454B | Blend | 466 | 78.1 °C |
| R513A | Blend | 573 | 95.2 °C |
| R717 Ammonia | Pure fluid | 0 | 132.4 °C |
| R718 Water | Pure fluid | 0 | 373.9 °C |
Property data generated offline with CoolProp and shipped as embedded JSON – the app interpolates at runtime, without a network connection.
Soon in your pocket.
Free, offline, no sign-up. The App Store launch is just around the corner.
Coming soon to the App Store
The results are for professional orientation and do not replace a safety-relevant design. In particular, the cooling load is a quick estimate (additive model without thermal inertia), not a substitute for a standards-compliant load calculation.