Confirm the manual or equipment specification before buying.
Free coolant tools and calculators: private, with no sign-up. Every calculation runs in your browser. Each tool answers one practical question about coolant and shows where its data comes from, so you can check it yourself.
Which tool should I use?
- Find my car coolant: start with this if you need to buy coolant for a car. Enter the spec code from your owner's manual (for example a Ford, GM or VW code). It lists products whose makers say they meet or are approved to that code, each linked to its product page. You can also browse by make or chemistry, but treat those results as guidance only.
- Compare coolants: pick two to four products from the coolant directory to see their published chemistry, glycol, colour, form, OEM approvals, ASTM standards, service-life claims and freeze points side by side. It also shows which spec codes they share. The page address updates, so you can share or bookmark a comparison.
- Freeze & boil point calculator: enter an ethylene- or propylene-glycol concentration to estimate freeze and boil points. It interpolates published Engineering ToolBox tables. For example, a 50% ethylene-glycol mix comes out at about −37 °C freeze and 107 °C boil at atmospheric pressure. A pressure cap raises the real boiling point.
- Coolant mixing checker: pick the technology already in your system (IAT, OAT, HOAT, P-HOAT, Si-OAT) and the one you want to add. It tells you whether mixing is usually acceptable or not recommended, and what to do next. It works by technology, not colour.
- Data-center coolant comparator: for liquid-cooled servers rather than cars. It filters PG25 and immersion fluids by supplier, base fluid and publicly reported qualifications, with links to each supplier profile and source.
Sharing results
The finder and the compare tool save your choices in the page address, after a # sign. You can bookmark or send that link, and it reopens the same results. Nothing you enter is sent to a server to calculate the answer.
How the data is collected
Product data comes from manufacturers' own product pages, technical data sheets and approval lists, and each product page links its sources. Car specifications come from carmakers' owner's manuals and parts catalogues. Physical properties come from published engineering tables. We don't publish prices, because they change too quickly to keep accurate. If a manufacturer changes a product, the tools reflect it only after the site is next updated, so check the label before you buy.
Limits of these tools
These tools give general information and are not a diagnosis. They can't see your vehicle's history, what is actually in your system, or whether a product's stated approval still applies to your model year. Your owner's manual and the product label always take priority. If your engine is overheating, losing coolant or showing oil in the coolant, see a qualified mechanic. A tool can't help with those problems. Coolant.com is independent and not affiliated with any brand listed.