Antifreeze Ratio Calculator - Coolant Mix for Freeze & Boil

Automotive Tools

Quickly calculate the ideal antifreeze-to-water ratio for your vehicle based on climate and current mix. Helps prevent freezing in winter and overheating in summer.

How to Use Antifreeze Ratio Calculator - Coolant Mix for Freeze & Boil

Choose your climate condition (standard, hot weather, cold weather, or custom), select your coolant type, and enter your current mixture (if known). The calculator will tell you how much coolant or water to add or drain to achieve optimal protection.

Frequently Asked Questions

What is the best antifreeze mix for most cars?

A 50/50 mix of antifreeze and distilled water is the standard recommendation for most climates, offering freeze protection down to -34°F and boil protection up to 265°F.

What if I live in a very cold or hot area?

For extremely cold climates, a stronger antifreeze mix (60/40 or 70/30) may be needed. In hot areas, a slightly higher water content can improve heat transfer. This tool helps you adjust safely.

Can I use tap water in my coolant system?

Distilled water is always recommended to avoid minerals that can corrode your cooling system. This tool assumes you’re using distilled water.

Why does coolant type matter?

Different coolants (ethylene glycol vs. propylene glycol) have different freeze and boil points. Our calculator accounts for this so you can select the right mix.

How do I test my current coolant mixture?

You can use an inexpensive antifreeze tester (hydrometer or refractometer) to determine the freeze point of your existing coolant. Input that into the calculator for custom recommendations.

Can this tool be used for all vehicles?

Yes, this tool applies to nearly all gasoline and diesel vehicles with liquid cooling systems. Always consult your vehicle manual for manufacturer-specific recommendations.