Stanford Sleepiness Scale

This is a quick way to assess how alert you are feeling. If it is during the day when you go about your business, ideally you would want a rating of a one. Take into account that most people have two peak times of alertness daily, at about 9 a.m. and 9 p.m. Alertness wanes to its lowest point at around 3 p.m.; after that it begins to build again. Rate your alertness at different times during the day. If you go below a three when you should be feeling alert, this is an indication that you have a serious sleep debt and you need more sleep.

Scale/RatingDegree of Sleepiness
Feeling active, vital, alert, or wide awake………………………………………………………..
Functioning at high levels, but not at peak; able to concentrate…………………………………..
Awake, but relaxed; responsive but not fully alert…………………………………………………
Somewhat foggy, let down…………………………………………………………………………
Foggy; losing interest in remaining awake; slowed down………………………………………….
Sleepy, woozy, fighting sleep; prefer to lie down………………………………………………….
No longer fighting sleep, sleep onset soon; having dream-like thoughts…………………………..
Asleep……………………………………………………………………………………………..