Checking your oil takes five minutes and tells you if your engine has enough to run safely
You check your oil by pulling out the dipstick, wiping it clean, reinserting it fully, then pulling it out again to read the level against the markings on the stick. The oil should reach the "full" line or fall between the "full" and "low" lines. If it is below the low line, you add oil of the type your car manual specifies. Most cars need checking once a month or before a long drive, though some newer vehicles with electronic oil monitors do not need manual checks.
Checking your oil is different from changing it. An oil change removes old oil and replaces it with fresh oil plus a new filter. Checking your oil is a quick inspection you do yourself between changes to make sure the level has not dropped dangerously low. A low oil level can mean your engine is burning oil faster than normal, or that a small leak has developed — either way, you want to know before the engine runs dry.
Key Takeaways
- You check oil with the engine off and the car parked on level ground, using the dipstick located under the hood.
- Wipe the dipstick clean the first time, reinsert it fully until it seats, then pull it out again to read the true level.
- Oil should reach the full line or sit between the full and low marks; if it is below low, add the oil type listed in your owner's manual.
- Check your oil monthly or before highway trips, though some newer cars have electronic monitors that alert you instead.
- A dipstick reading below the low line does not mean you need an oil change — it means you need to add oil now.
Where to find the dipstick under your hood
Open your hood and look for a thin rod with a yellow or orange handle, usually located near the front or side of the engine. The handle is often labeled "Oil" or shows an oil can symbol. If you cannot spot it, check your owner's manual for the exact location — it varies by make and model.
On some newer vehicles, there is no dipstick at all. Instead, the car has an electronic oil level monitor that displays a reading on your dashboard. Check your manual to see which type your car has. If your car has no dipstick and no electronic monitor, you will need to have the oil level checked at a service station.
The correct steps to read the dipstick
Park your car on level ground and turn off the engine. Wait a few minutes for the oil to settle — if you check when ready after driving, the reading will be inaccurate because oil is still circulating through the engine. Pull out the dipstick by grasping the handle and drawing it straight out.
Wipe the dipstick clean with a paper towel or clean rag. This first wipe removes the oil coating so you can see the actual level on the second reading. Reinsert the dipstick all the way until it seats fully in its tube — you should feel it stop. Pull it out again slowly and hold it horizontal or at a slight angle so the oil does not run off the end.
Look at where the oil reaches on the stick. Most dipsticks have two marks: a "full" line and a "low" or "minimum" line. The oil should reach the full line or fall somewhere between the two lines. If the oil level is below the low line, you need to add oil.
What to do if your oil level is low
If the dipstick shows the oil below the low line, you will need to add oil. Check your owner's manual for the correct oil type — this is usually listed as a viscosity grade like 5W-30 or 10W-40. Using the wrong type can affect engine performance and fuel economy. Buy a quart of the correct oil from any auto parts store or gas station.
Open the oil filler cap on top of the engine — it is usually labeled with an oil can symbol and twists off by hand. Pour in about half a quart, then wait a minute for the oil to drain down into the pan. Check the dipstick again using the two-wipe method. Add more oil in small amounts until the level reaches the full line or the middle of the range between full and low.
Do not overfill. Oil that sits above the full line can damage the engine seals and cause leaks. Once you reach the correct level, replace the oil filler cap and close the hood. Keep track of how often you add oil — if you are adding more than a quart every month, have a mechanic check for a leak or excessive oil burning.
How often you should check your oil
Most manufacturers recommend checking your oil once a month or before any long road trip. If your car is older, burns oil quickly, or has high mileage, check it more often — every two weeks or before each drive. Newer cars with electronic oil monitors may not need manual checks at all, though reading your manual will tell you what your specific car requires.
If you notice the oil level dropping quickly between checks, or if your engine is making a knocking sound, have the car inspected by a mechanic. A rapid drop in oil level can signal a leak, worn piston rings, or a failing gasket — all things that need professional attention before they cause engine damage.
The difference between checking oil and changing oil
Checking your oil is a five-minute inspection that tells you whether the current oil level is safe. Changing your oil is a more involved service where old oil is drained out, the oil filter is replaced, and new oil is poured in. You check your oil between changes to catch problems early. An oil change typically happens every 3,000 to 10,000 miles depending on your car and the type of oil, but you should check the level much more often.
Think of checking oil like checking your tire pressure, and changing oil like replacing a tire. One is a quick safety check; the other is a scheduled maintenance service. Both matter, but they serve different purposes.
Frequently Asked Questions
Can I check my oil while the engine is hot?
You can, but the reading will be less accurate. Hot oil expands and sits higher on the dipstick than it will once the engine cools. For the most reliable reading, check the oil when the engine is cold or has been off for at least five minutes. If you must check a hot engine, be careful not to touch the dipstick tube or engine parts, as they will be very hot.
What does it mean if the oil looks dark or dirty?
Dark oil is normal — oil darkens as it circulates through the engine and picks up particles. This is not a sign that you need an oil change when ready. However, if the oil looks thick, gritty, or has a burnt smell, it may be time for a change sooner than scheduled. Your owner's manual will tell you the recommended oil change interval for your car.
Do I need to check oil if my car has an electronic monitor?
Most newer cars with electronic oil level monitors do not require manual dipstick checks. The system will alert you on the dashboard if the oil level drops below safe. However, some drivers still prefer to check manually as a backup. Check your owner's manual to see whether your car recommends manual checks in addition to the electronic system.
What if I cannot find the dipstick?
Some newer vehicles do not have a traditional dipstick. Check your owner's manual first — it will tell you whether your car has a dipstick, an electronic monitor, or neither. If your car has none of these, you will need to have the oil level checked at a service station or dealership during routine maintenance.
Can I add oil without checking the dipstick first?
You can, but it is not recommended. Adding oil without knowing the current level risks overfilling, which can damage engine seals and cause leaks. Always check the dipstick first to see how much oil you actually need. Adding a little at a time and rechecking is safer than guessing.