Which? experts have tested 40 dashcams to find the most reliable models. These are the best buys from £70

The question What, actually, does a dash cam do? Well, these nifty cameras sit – no surprise – on the dashboard of your car, constantly recording video footage of your driving. That way, if you were to get into an accident, you could submit the recordings as evidence of your innocence. Sounds super, but which are best to buy?

The basics Which? experts tested 30 dash cams: from a £40 Orskey version to one costing £530 by BlackVue.

The method The whizzes at Which? attached each product to a car and drove – both in daylight and in darkness – along a fixed route, over a range of minor and major roads, replete with various hazards, junctions and roundabouts. Then they assessed the quality of the recordings, gauging how sharp the image was; whether the footage was shaky or clear; if the audio was loud or quiet; and how much of the road was in the frame. Lastly, to make sure you don’t have to faff around with your dash cam each time you drive, they considered how straightforward each product was to set up and use.

The thing to remember Which? buys the products before testing them, which means no freebies and no biased results.

Find the full range of expert reviews at which.co.uk/dash-cams

BEST VALUE

What works? Lots. Testers found this was very straightforward to set up and produced bright, high-quality footage. It worked well at night and in the daytime, too. Plus, obviously, it’s cheap.

What’s the catch? Design-wise, it’s a little bulky, which some drivers might find intrusive.

BEST MID-RANGE 

What works? Again, this was simple to set up and caught clear footage in the daylight. It also had good audio recording, accurate GPS and an ultra-wide-angle camera, so you can see everything that’s going on surrounding your car.

What’s the catch? The night-time footage was slightly blurry.

BEST BLOWOUT 

What works? Quality-wise, this was tip-top: testers found the footage was smooth, crystal-clear and detailed enough to capture other cars’ number plates, in daylight or darkness. It also had good audio and pinpoint GPS.

What’s the catch? It was a little finicky to attach to the windscreen. Also, despite being uber-pricey, to access the majority of ‘smart features’ you need to pay an extra £9.99 a month.