What is so complicated about oven temperature? Doesn’t 350° F measured in Boston or Dubai or Sydney stay the same . While that is true the game changes when you decide to travel a few thousand miles (often times even less) and get homesick , decide to make your favorite fruit pie / tart/ roast , and goes to pre-heat the oven. It looks like a working oven , but speaks a different language – who thought heating an oven can be complicated !
Looking for the chart ? Click here .
Imagine this you are in that charming cottage in the middle of nowhere, enjoying the solitude and at dinner time goes to bake that frozen pizza and it says – Gas Mark ??
This is not just a traveler’s dilemma , have you tried deciphering an old fashioned recipe and wondered “They really wanted to keep this a secret, didn’t they ! “. If you ever had that perplexed / frustrated feeling – this is the post for you.
And technology has recently added to the confusion with the convection ovens – these are the ones with a fan. Remember those GE commercials where the oven cooked at light speed and you had enough time to make the entire thanksgiving dinner and get to the game with plenty of time to spare ?
You DON’T !!!! Well well well you are lucky to be so YOUNG !!!
Now I am not going to go into the details of why there are 2 (in fact 3 , but in cooking you won’t encounter the 3rd , at least for now ) , scales for measuring temperature. The fact of the matter is if you are a baker chances are you have had to convert the unit of temperature in a recipe at least once.
The main unit of temperature measurements are fahrenheit (°F) and celsius (°C). Most of the world measures temperature in celsius units while US and a handful of other countries continue to use fahrenheit . As my oven is calibrated in F that is the most common measurement I use , but many of my readers follow the metric system. So often times I find myself giving both measurements.
How to Do I convert F to C or visa versa ?
Remember middle school science ? I am pretty sure many of us had to memorize this formula
C= (F – 32) X (5/9) or
F = C X (5/9) – 32
Where C is the temperature in celsius and F is in fahrenheit.
There is a quick way too – just type f to c in google (or ask your virtual assistant to do that for you) and a handy dandy calculator will pop up.
Ok but my oven says Gas Mark !
“What the heck is that “- these were my actual thoughts when I encountered it the first time. C I understood , F I lived with , but Mark ? that too with Gas ?? No no no no no no !
Many of us did not start our culinary journeys with appliances marked this way. So it took a little bit of digging. Here is what I understood. Apparently gas marks referred to the calibrations on the oven control knob . These are in steps of 25°F (obviously pre- metric era ) with Mark 1 starting at 275°F . I am not going to go into the details of how to convert these to C or F . Just refer to the table below for the most common temperatures you encounter in baking.
Fan or Convection – Can There Be More Confusion ?
The fan or the convection ovens came into the home kitchens fairly recently. It is in fact your conventional oven with a fan that forces the air in the heating chamber to circulate faster. This maintains heat evenly inside reducing common problems like hot spots. As a result food cooks faster.
When converting a regular recipe to a convection oven recipe it gets a little trickier. So these are just guidelines . Here are your options – one to leave the recipe temperature as is and reduce cooking time or reduce the temperature and cook for the time mentioned in the recipe.
In short if the recipe is written for conventional oven reduce
- the Temperature 25 to 30 °F or by 15 to 20 °C and cook for the same time
- or
- the cook time by 25 % if measuring in F or 30 % if measuring in C .
There are some who reduce both as well. But as a standard I try to change the temperature and leave the time as is.
Too much to remember ? Here is a handy dandy reference chart –
| F | F (Fan) | C | C(Fan) | Gas Mark | General Terms |
| 250 | 225 | 130 | 110 | ½ | Very Cool/ Very Slow |
| 275 | 250 | 140 | 120 | 1 | Very Cool/ Slow |
| 300 | 275 | 150 | 130 | 2 | Cool/ Slow |
| 325 | 300 | 165 | 145 | 3 | Very Moderate/ Warm |
| 350 | 325 | 175 | 155 | 4 | Moderate |
| 375 | 350 | 190 | 170 | 5 | Moderate |
| 400 | 375 | 200 | 180 | 6 | Moderately Hot |
| 425 | 400 | 220 | 200 | 7 | Hot |
| 450 | 425 | 230 | 210 | 8 | Hot |
| 475 | 475 | 245 | 225 | 9 | Hot / Very Hot |
| 500 | 475 | 260 | 240 | 10 | Very Hot |
Download the printable version
Note :
- The figures are rounded to nearest 5 or 10s for ease of use.
- Where digital temperature settings are not possible usually the temperature is rounded up to the nearest 10 – ex. 165 °F will be set at 170° F.
- Convection temperatures are approximated keeping the original cooking time in mind.
John Thyden
Friday 16th of April 2021
I'm trying to bake two items. One should be baked @ 300, the other @ 350. I have two convection ovens so I could just use both of them. If I wanted to use only one, how would I go about computing the time required to bake the one that usually takes 350, but us