How hot Low and High get
A slow cooker is a glazed stoneware pot inside a housing with a heating element wrapped around it. The lid lets condensation run back down and forms a water seal, so heat and moisture stay in. The University of Kentucky Cooperative Extension gives these ranges for the two standard settings:
| Setting | Food cooks at (°F) | In °C |
|---|---|---|
| Low | 200 to 240°F | 93 to 116°C |
| High | 300 to 340°F | 149 to 171°C |
Both are cooler than a typical oven setting. A recipe baked at 350°F (177°C) sits about 10 degrees above the top of the High range and 110 degrees above the top of Low. That gap is why a slow cooker needs hours where the oven needs minutes. Some models have extra settings between Low and High, and the extension notes that the High setting can caramelize food and let it dry out. For converting oven dials between Fahrenheit, Celsius and gas marks, use the oven temperature converter.
Low versus High: the factor of two
The Kentucky publication gives a rule of thumb: cooking on Low takes about twice as long as cooking the same recipe on High. That makes switching settings simple arithmetic.
| Recipe says Low | About the same on High |
|---|---|
| 4 hours | 2 hours |
| 6 hours | 3 hours |
| 8 hours | 4 hours |
| 10 hours | 5 hours |
| 12 hours | 6 hours |
It is a rule of thumb, not a law. Your cooker, how full it is and how cold the food was at the start all move the result. The publication says the most useful thing you can learn is the pattern of your own cooker: after a few recipes you know whether it runs fast or slow.
Oven or stovetop to slow cooker
Texas A&M AgriLife Extension, on its Dinner Tonight site, gives a single conversion point and one example:
| Original recipe | Slow cooker Low | Slow cooker High |
|---|---|---|
| 1 hour simmering on the stove | 8 to 10 hours | 4 to 6 hours |
| 1 hour baking at 350°F | 8 to 10 hours | 4 to 6 hours |
| 30-minute oven roast | about 4 to 5 hours in total | setting not given |
The 8 to 10 hours on Low and 4 to 6 hours on High also agree with the Kentucky factor of two: half of 8 to 10 is 4 to 5, inside the High range. Neither source gives a formula for scaling longer oven times, so treat the one-hour row as the anchor and check doneness at the short end of the range.
Cut the liquid
Because a slow cooker traps steam, the same Texas A&M page says you may need to reduce the liquid. Its example: if the original calls for 6 to 8 cups of water, start with 5. If the original has no liquid at all, add 1/2 cup of water or broth to make some steam in the crock. The Kentucky publication adds the other side: for meat, the water or stock should almost cover it, so heat moves into the meat well.
Layering and preheating
Vegetables cook more slowly in a slow cooker than meat, so the Kentucky publication says recipes put them in the pot first, with meat on top, and cut them into small pieces. It also suggests starting as hot as possible: brown the meat first, or preheat the pot with boiling water.
Slow cooker to oven
Running the Texas A&M rule backwards gives the oven version: a dish that takes 8 to 10 hours on Low or 4 to 6 hours on High corresponds to roughly 1 hour at 350°F. Two things change when you move it to the oven:
- Moisture. The slow cooker recipe was written with less liquid because the lid seals in steam. In an open or loosely covered oven dish more of it evaporates, so you may need to add back some of the liquid the slow cooker version left out, or cover the dish.
- Doneness, not time. The oven time is an estimate from a single conversion point. Check meat with a thermometer. The meat cooking time calculator lists roasting times by weight together with safe internal temperatures for beef, pork, lamb and chicken.
If the goal is shorter still, the air fryer conversion calculator turns an oven setting into a lower air fryer temperature and a shorter time. That works for pieces that fit in a basket, not for stews and braises.
Food safety while it heats up
The risk in slow cooking is the slow start. The Kentucky publication puts it in three temperatures:
| Temperature | Target | Why |
|---|---|---|
| 125°F (52°C) | within 3 hours | temperature at which heat begins to destroy bacteria |
| 140°F (60°C) | within 4 hours | below this some bacteria can survive |
| 158°F (70°C) | held at least 1 hour | the publication gives this to kill all bacteria |
Before buying a cooker, the publication suggests checking consumer buying guides for whether a model reaches 125°F within 3 hours on Low. Its handling rules:
- Keep raw ingredients in the refrigerator until they go into the cooker.
- Thaw frozen meat or poultry before cooking.
- Cut vegetables in small pieces so heat moves in quickly.
- Do not overload it. Most slow cookers are designed to be about half full.
- Do not lift the lid to peek or stir. Each time you uncover the pot you lose enough heat to slow cooking by thirty minutes or more.
- Do not leave cooked food to cool down in the pot. Eat it or cool it fast and refrigerate it.
- Never reheat leftovers in the slow cooker.
Conversion checklist
- Find the oven or stovetop time. One hour at 350°F becomes 8 to 10 hours on Low or 4 to 6 on High.
- Pick the setting. Low takes about twice as long as High.
- Reduce the liquid: 6 to 8 cups becomes about 5; none becomes 1/2 cup.
- Thaw meat, cut vegetables small, put vegetables at the bottom.
- Fill to about half, put the lid on, and leave it on.
- Check doneness with a thermometer at the short end of the time range.
Frequently asked questions
How do I convert an oven recipe to a slow cooker?
Texas A&M AgriLife Extension gives one rule: 1 hour of baking at 350°F or simmering on the stove equals 8 to 10 hours on Low or 4 to 6 hours on High. Cut the liquid too, because the slow cooker traps steam; if the recipe calls for 6 to 8 cups of water, start with 5.
How do I convert a slow cooker recipe to the oven?
Run the same rule backwards: a recipe that needs 8 to 10 hours on Low or 4 to 6 hours on High corresponds to about 1 hour at 350°F. Check doneness with a thermometer rather than the clock, and expect to need the liquid the slow cooker version saved, since an oven dish is not sealed the same way.
How hot is Low and High on a slow cooker?
The University of Kentucky Cooperative Extension says Low generally means the food cooks at 200 to 240°F and High at 300 to 340°F. Models differ, and some have settings in between.
Is Low twice as long as High?
As a rule of thumb, yes. The Kentucky Extension publication says cooking on Low takes about twice the time of the same recipe on High. An 8-hour Low recipe is therefore about 4 hours on High.
Can I put frozen meat in a slow cooker?
The Kentucky Extension publication says to thaw frozen meat or poultry before cooking. The slow cooker heats up slowly, and the food has to pass through the temperatures where bacteria survive quickly enough.
Sources
- University of Kentucky Cooperative Extension, FN-SSB.003 Putting Your Slow Cooker to Work, revised January 2018 (Low 200 to 240°F, High 300 to 340°F; Low about twice as long as High; lifting the lid costs thirty minutes or more; 125°F within 3 hours, 140°F within 4 hours, 158°F for at least an hour; thaw frozen meat; half full; never reheat leftovers in the slow cooker)
- Texas A&M AgriLife Extension, Dinner Tonight: How to Convert a Recipe for the Slow Cooker (1 hour at 350°F or simmering = 8 to 10 hours on Low or 4 to 6 on High; 30-minute roast about 4 to 5 hours; reduce liquid, 6 to 8 cups becomes 5; add 1/2 cup if there is none)