Turbo Boost Horsepower Calculator
Power gain from boost pressure, with intercooler losses.
Enter your values
Enter the naturally aspirated power in hp.
Enter the boost pressure in psi.
Choose one of: Ideal / water-methanol, Good front-mount, Small or hot intercooler, No intercooler.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Estimated boosted power
- 313 hp
- Pressure ratio
- 1.68:1
- Gain over NA
- 113 hp (56.3%)
- Air mass increase
- 68%
Quick answer
Boosted power scales with absolute pressure ratio: hp_boost = hp_NA × (boost + 14.7) ÷ 14.7, reduced slightly by charge heating.
hp = hp_NA × (psi + 14.7) / 14.7 × efficiency
At a glance
| What it does | Power gain from boost pressure, with intercooler losses. |
|---|---|
| Category | Auto |
| Inputs needed | Naturally aspirated power, Boost pressure, Intercooling |
| Main output | Estimated boosted power |
| Formula | hp = hp_NA × (psi + 14.7) / 14.7 × efficiency |
| Cost | Free — no sign-up, no download |
How to use the Turbo Boost Horsepower Calculator
- 1Enter the engine's power without boost.
- 2Enter peak boost in psi (1 bar = 14.5 psi).
- 3Choose how well the charge air is cooled.
Inputs explained
- Naturally aspirated power(hp)
- Enter the naturally aspirated power in hp.
- Boost pressure(psi)
- Enter the boost pressure in psi.
- Intercooling
- Choose one of: Ideal / water-methanol, Good front-mount, Small or hot intercooler, No intercooler.
Worked example
Using the values the calculator loads with:
Inputs
- Naturally aspirated power200 hp
- Boost pressure10 psi
- IntercoolingGood front-mount
Results
- Estimated boosted power313 hp
- Pressure ratio1.68:1
- Gain over NA113 hp (56.3%)
- Air mass increase68%
Frequently asked questions
Is 10 psi a lot of boost?
On a stock engine, 6–10 psi is a common safe range. Above that you generally need forged internals, better fuel and careful tuning.
Why does an intercooler add power?
Cooler air is denser, so the same pressure carries more oxygen. A good intercooler recovers 7–15% of the power lost to charge heating.
What do I need to enter into the Turbo Boost Horsepower Calculator?
Just 3 values: naturally aspirated power, boost pressure, intercooling. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Turbo Boost Horsepower Calculator work out the answer?
Boosted power scales with absolute pressure ratio: hp_boost = hp_NA × (boost + 14.7) ÷ 14.7, reduced slightly by charge heating. It applies the formula hp = hp_NA × (psi + 14.7) / 14.7 × efficiency and shows the working so you can check each step by hand.
Is the Turbo Boost Horsepower Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.