What is the best way to check the seal on an oven door?

To check the seal on an oven door, the best way is to place a sheet of paper between the door and the oven. Close the paper and try to pull out the paper from the door. if you are able to pull out the paper, then there is a space in the seal and if you are unable it means there is no space in the seal. Turning on the oven and feeling for escaping heat is not a safe method to check the seal of an oven door.

Turning on the oven light and see if the light escapes from another door is not the best way to check the seal as it is possible to miss small space that might be difficult to see with the naked eye.