Inverter Size Calculator
Pick the right inverter wattage for your peak load.
About the Inverter size calculator
Use this inverter size calculator for van leisure battery & solar setup. Pick the right inverter wattage for your peak load.
Enter your inverter size details
The biggest thing you'll run for more than a few seconds.
2× for resistive, 3–6× for motors / compressors.
Pure sine vs modified
Anything with a motor, compressor or sensitive electronics needs pure sine. Modified sine is fine for kettles and heaters but will damage some chargers.
Your inverter size results
Recommended continuous
1,000 W
+25% headroom
Surge needed
1,600 W
2× starts
Buy this size
1000 W
≈ 93 A on 12 V DC
Why inverter size matters for van leisure battery & solar setup
Plan with confidence
Getting your inverter size numbers right early avoids costly rework, undersized components and surprises on the road.
Related battery & solar tools
Pair this with the rest of our battery & solar calculators to plan your full van conversion.
Inverter size calculator FAQ
- What does the Inverter Size Calculator do?
- Pick the right inverter wattage for your peak load. It is designed for van leisure battery and solar so you can plan with confidence.
- Is the inverter size calculator free to use?
- Yes. All VanTools calculators, including the Inverter Size Calculator, are free to use with no sign-up required.
- How accurate are the inverter size results?
- Results are estimates based on the values you enter and standard van leisure battery and solar assumptions. Always sanity-check against manufacturer data and your real-world conditions.
- Can I share or save my inverter size calculation?
- Yes. Use the Share button to copy a link that includes your inputs, or use Export to download a PDF or image of your results.