Everything you need to know about how dash cams handle storage
While dash cams differ in design, features, video resolution, and pricing, there’s one thing that makes them similar to each other – the need for storage through a micro SD card. In this article, we’ll go over the factors to consider when choosing a micro SD card, while providing you a projection of the estimated recording hours for our best-selling dash cams.
An SD (Secure Digital) card is a compact, portable storage device that is commonly used to store data such as images, movies, and music in devices such as cameras, dash cams, smartphones, and tablets.
SD cards are useful because they allow for the easy transmission of data between devices as well as the storage of data when the device's internal storage is full. They can also be removed and replaced with a larger card, or stored separately as a backup.
With dash cams, we usually use a microSD card which is used in smaller electronic devices, though it may be used in any SD card slot with an adapter.
The best MicroSD cards to use for your dash cam should be at least a class 10 rank for speed and durability
The storage space requirement increases as the resolution gets higher. 4K images occupy much more space than 2K QHD, as it consumes more than full HD or 1080p images. This is also the reason why 4K dash cams like the VIOFO A139 Pro have maximized its storage space up to 512GB. Higher resolutions will also be more taxing on your SD card, so make sure you select an SD card that can handle that resolution with high-speed data writing.
Typically, recording one hour of 1080p video consumes around 6GB of storage. If you drive for two hours per day, five days a week, you would need approximately 64GB worth of memory.
If you’ve wired for parking mode, this will involve the camera recording for much longer to keep your vehicle protected, although in a mode to conserve space, either through only recording impact and motion, or at a lower frame-frate.
Consider the maximum storage capacity of your dash cam. New 2K dash cams, particularly those from VIOFO such as the A229 Plus and the A119 Mini 2 have increased their capacity to 512 GB, while some other cameras only have a 256GB maximum.
Moreover, dash cam memory cards undergo multiple overwrites. A larger memory capacity reduces the frequency of write-cycles and prolongs the card's lifespan.
When it comes to dash cam footage, the type of video file compression used can significantly impact both video quality and storage requirements. H.264 and H.265 are two common compression formats, with H.265 being the newer and better option.
H.264, also known as AVC (Advanced Video Coding), is widely used for its balance between video quality and file size, making it efficient for most dash cam recordings. However, HEVC (High-Efficiency Video Coding), or H.265, offers even better compression, reducing file sizes by up to 50% compared to H.264 while maintaining, and sometimes improving, video quality. This means longer recording times on the same storage space and clearer footage, especially in high-resolution formats like 4K. However, some old computers and phones can struggle with processing H.265 videos. New BlackVue dash cams, allow users to choose between H.264 and H.265 options. Check out our dedicated page for more information on H.264 vs H.265.
When selecting an SD card for your dash cam, it’s crucial to choose one with the appropriate speed rating to ensure reliable performance. Look for a Class 10 or UHS-I (U1) rating, which guarantees a minimum write speed of 10MB/s, which will work for all cameras rated 4K and below. Typically, a 4K camera records approximately 3.75MB/s. A 2K camera records at about 2.5MB/s, combining to roughly 6.25 MB/S total, making a Class 10 card(10MB/s) ideal.
That being said, “faster SD cards” won’t necessarily improve video quality, nor durability. Remember: dash cams don’t require the highest speed rating - rather, they require something reliable that meets the requirements of the image quality.
Of course, the size of the SD card will still vary depending on how you use your dash cam. Here’s a list of our recommended sizes:
