Maintenance

AC Refrigerant Charge Calculator

Calculate AC refrigerant charge levels and target pressures. See if your system is undercharged and estimate DIY recharge costs.

Quick Presets

Results

Enter AC system specs to check charge level

Refrigerant Types

R134a — Most vehicles 1994-2015
R1234yf — Most vehicles 2015+
R12 — Pre-1994 (requires certification)

How to Use

Find system capacity on underhood label
Estimate current charge (or use gauge)
Enter current outside temperature
Select your refrigerant type

FAQs

Can I mix refrigerant types?

Never. Mixing refrigerants causes chemical reactions that can damage the compressor and contaminate the entire system. Always use the specified type.

Why does my AC need recharging?

AC systems slowly lose refrigerant through seals and hose permeation. If you need frequent recharges, you likely have a leak that should be repaired.

Can I overcharge my AC?

Yes, and it's common with DIY recharges. Overcharging reduces cooling efficiency and can damage the compressor. Use gauges and stop when pressures are correct.

Should I add stop-leak?

Generally not recommended. Stop-leak can clog system components and makes professional repair more difficult. It's better to find and fix the actual leak.

Limitations

Target pressures are estimates
Does not detect leaks
R1234yf should be professionally serviced
Some vehicles have specific procedures

AC Refrigerant Charge Calculator

System Specifications

Conditions

Quick Presets

Results

Target Pressures (at current temp)

Recommendations