Dash cams are a great tool for proving who was at fault in a collision, whether you're driving or parked. As resolutions and quality improves each year, files are getting larger and larger.

A single minute of footage from a 4K dash cam, for example, is around 400MB. Most email services won’t let you attach any file larger than 15 or 20MB, making it impossible to email your footage to your insurance company, the police or anyone else.

But there are a few things you can do, and we’ll explain all the options.

How do I transfer dash cam video to a computer?

First, in case you’re not even at the stage where you’ve got the appropriate file, the simplest way for most people is to remove the dash cam from your car and connect it to your computer – PC or Mac – with a USB cable that came in the box.

It should behave like a USB flash drive, so you can see the folders and individual video files. You might need to try opening different folders if the names aren’t obvious.

How to send large dash cam videos

If the file you’re after isn’t in the main ‘videos’ folder or similar, then check ‘protected’, as this is where files are put if an impact is detected by the dash cam while recording the file: this prevents it being overwritten (and therefore lost) when the memory card becomes full.

Typically, the filenames contain the date and time, so as long as you know when the incident occurred you should be able to find the clip fairly easily.

How to send large dash cam videos

Dash cams are usually set to record each minute or two of video as a single file to keep file sizes down.

Just right-click on the file with the right date, choose copy and then paste it to a folder on your computer.

Double-clicking it should play the video in the default app, so you can watch and confirm it does contain the incident.

Send dash cam video via WeTransfer

The quickest option, if your insurer allows it, is to use a file transfer service such as WeTransfer or a cloud storage service like Dropbox, Google Drive or Microsoft OneDrive.

Once uploaded, which could take a while depending upon your internet speed, you will get a link which you can email to whomever you need to share the video with.

How to send large dash cam videos

When they click the link, the file will be downloaded to their computer.

Send dash cam video in the post

If your insurer, as many do, requires the original file and won’t accept an online transfer, you’ll have to burn it to a CD (you’ll need a blank CD or DVD and a CD/DVD writer) or copy it to a USB stick which you can then send in the post.

Use a video editor

If you absolutely have to email the file, then you’ll need to edit the clip to just the few seconds when the incident happens.

It’s worth including a few seconds before and after to give context.

Here’s how to use the built-in video editor in Windows 10, but you can of course use any video editor. There are lots of great free options including DaVinci Resolve.

After ‘trimming’ the clip to remove the portion before and after the incident, you need to save the clip, which in video editors, is called rendering.

How to send large dash cam videos

There will be options to pick the resolution and other settings, and it’s best to either match the original clip settings (which will probably be 1920x1080 at 30 frames per second) or use a preset.

Once saved, you’ll find out if the file is small enough to email. If still too large, trim more off the start and end of the clip and, when saving, choose a lower ‘bitrate’ number than before if you have that option.

Use the dash cam app

Some dash cams have Wi-Fi and a companion app that you can download from Google Play or the iPhone App Store.

This usually includes a way to download individual clips from the dash cam while it’s still in the car. You might even find the option to select the portion of the clip you need, or a tool to trim the clip after it has been transferred to your phone.

How to send large dash cam videos

In fact, once saved to your phone’s camera roll (or another folder) you should be able to use your phone’s Gallery or Photos app to edit the video so just the incident is included – just as with a PC or Mac video editor.

You can then try attaching the shorter video to an email in your phone’s email app. Again, you can use WeTransfer on your phone if the file is still too big to email: the app is available for both iOS and Android.

How to upload dash cam footage to police

How to send large dash cam videos

Dash cam maker Nextbase has created a website where UK drivers can share footage of incidents with the relevant police force. Head to the website - the National Dash Cam Safety Portal - select your region and click on the appropriate force. This will take you to the website of that local police force with instructions of how to share the video.

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