Find out when you will be safe to drive the morning after drinking.

We've created this app as part of the 'morning after' (http://www.morning-after.org.uk) drink drive campaign, which has been running for several years. The campaign is designed to help normally responsible people avoid the risk of a drink drive conviction - or worse still, cause a collision or casualties while ‘over the limit’ - by highlighting how long it takes for alcohol to pass through the body.

The app enables you to calculate roughly when it will be safe for you to drive the morning after drinking alcohol. And it can help you calculate when to stop drinking alcohol if you have to drive the following morning.

Let’s make one thing absolutely clear - this app is not intended to help you work out how much you can drink on a night out before driving home.

If you are drinking any amount of alcohol on a night out - even one drink - you should leave the car at home and make alternative arrangements.

And the app won’t help you if you are arrested for drink driving.

What it will do is enable you to calculate roughly when it will be safe for you to drive the morning after drinking alcohol. And it can help you calculate when to stop drinking alcohol if you have to drive the following morning.

How the calculator works

The app allows one hour for each unit of alcohol, plus an additional hour for the first drink to allow for the alcohol to enter the bloodstream. It then rounds up the calculation to the nearest half hour.

The app bases its calculation from the time you stop, not when you start drinking. Some people say this is over-cautious, but we’d rather be safe than sorry.

The 'hours before driving' calculation is not based on any drink drive limit - it is the length of time when the alcohol in the drinks you've consumed is likely to have passed through your body. This is when we suggest you will be 'safe to drive'.

How to use the app

Simply tot up the drinks you consumed the night before - or better still, use the app to keep track of what you’re drinking while you’re out - and the calculator will store them and give you a rough calculation of when you will be safe to drive.

We’ve included a fair number of drinks, but if you can’t find the exact drink you consumed there may be something of similar alcoholic content (ABV).

For more information about 'morning after' drink driving visit: http://www.morning-after.org.uk