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Fiscal horsepower calculator

Estimate a car's fiscal horsepower (CV) — French formula.

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Need Fiscal horsepower (CV)? The Fiscal horsepower calculator derives it from CO₂ (g/km), Engine power (kW) in one step. For instance, with CO₂ (g/km) = 120 and Engine power (kW) = 85 it returns Fiscal horsepower (CV) = 6.

How to use it

  1. Enter your values: CO₂ (g/km), Engine power (kW).
  2. Read the result instantly: Fiscal horsepower (CV).

Frequently asked questions

What does the Fiscal horsepower calculator actually compute?

It takes CO₂ (g/km) and Engine power (kW) and derives Fiscal horsepower (CV) from them. The calculation is live as you type, so the result updates on every change.

What information do I need to provide?

2 values: CO₂ (g/km) and Engine power (kW). Nothing else is required — no account, no file upload.

Can you show a worked example?

With CO₂ (g/km) = 120 and Engine power (kW) = 85, the calculator returns Fiscal horsepower (CV) = 6. Those figures come from running this exact tool, so you can reproduce them by entering the same values.

What happens if I enter larger values?

It moves a lot. Using CO₂ (g/km) = 240 and Engine power (kW) = 170 instead, Fiscal horsepower (CV) goes from 6 to 15 — which is why it is worth testing a few scenarios rather than trusting a single figure.

What does it give for smaller values?

Scaled down to CO₂ (g/km) = 60 and Engine power (kW) = 43, Fiscal horsepower (CV) comes out at 2. The relationship is worth checking at both ends before you rely on a single result.

When would I actually use this?

Deciding between two cars, or between keeping one and replacing it: fuel or charging, insurance, depreciation and what a kilometre really costs.

What is the most common mistake?

Comparing on fuel alone. Depreciation is usually the largest line in the first years and dwarfs the difference in consumption between two comparable cars.

How accurate is it, and what are the limits?

French fiscal-power formula — indicative.

What is the difference between the Fiscal horsepower calculator and the Horsepower calculator?

This one returns Fiscal horsepower (CV); the Horsepower calculator returns Power (HP) and Power (kW). That is the whole difference — open the one whose figure you need.

Is there a tool for the next step?

EV charging time calculator is the closest one after this: Estimate how long it takes to charge an electric vehicle between two battery levels.

Further reading

All guides →
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