Most people spend a lot of time choosing the right dash cam and almost no time thinking about the memory card that goes inside it. This is a mistake that costs drivers every year.
The wrong memory card does not just limit your recording time — it can corrupt footage, cause the camera to stop recording mid-journey, and in the worst cases, mean that you have zero usable footage when you actually need it.
Here is everything you need to know to choose the right card for your dash cam.
Why Regular SD Cards Fail in Dash Cams
Standard SD cards are designed for cameras and smartphones — devices that record intermittently, in bursts, and then sit idle. A dash cam is completely different. It records continuously, every time you drive, often in high temperatures inside a parked car.
This continuous write cycle destroys regular SD cards far faster than the manufacturer intends. A standard card used in a dash cam can fail within months. When it fails, it often corrupts the most recent footage first — exactly the footage you would need in an accident.
What to Look For — The Key Specifications
Endurance Rating
This is the most important specification for a dash cam memory card. Endurance is measured in TBW — terabytes written — and indicates how much data the card can handle before performance degrades. Look for cards rated at 1500 TBW or higher for reliable long term performance.
Speed Class
Dash cams require a minimum write speed to record without dropped frames. Look for:
• Class 10 or U1 — minimum for 1080p recording
• U3 or V30 — recommended for 2K recording
• V60 or V90 — required for 4K recording at 30fps or above
Using a card with insufficient write speed in a 4K camera will cause dropped frames, stuttering footage, and potentially camera errors.
Capacity
The right capacity depends on your camera's resolution and how often you want to manage the card:
• 32GB — suitable for 1080p cameras on short daily commutes. Loop recording activates quickly.
• 64GB — the recommended minimum for most drivers. Provides adequate buffer for typical daily use.
• 128GB — recommended for 2K and 4K cameras, long commutes, or drivers who want maximum footage retention before loop recording activates.
• 256GB and above — ideal for fleet vehicles, rideshare drivers, or anyone who wants the longest possible recording window.
Recommended Brands for Dash Cam Use
Not all memory card brands perform equally in dash cam conditions. The following brands consistently produce cards rated for continuous recording:
• Samsung PRO Endurance — specifically designed for continuous recording applications. Excellent heat resistance and reliability.
• SanDisk High Endurance — widely used in dash cams and security cameras. Good value for money with strong endurance ratings.
• Microdrive Professional — high performance cards with strong write speeds. Good option for 4K recording.
How Often Should You Replace Your Memory Card?
Even endurance-rated cards have a finite lifespan. As a general guide:
• Light use — one to two short drives per day — replace every two to three years
• Moderate use — regular daily commuting — replace every one to two years
• Heavy use — long daily drives, multiple trips, or commercial use — replace annually
Signs that your card needs replacing include: the camera taking longer than usual to start recording, footage files that will not play back, error messages from the camera, or the camera failing to detect the card.
The Bottom Line
Your memory card is as important as the camera itself. The best dash cam in the world is useless if the card inside it fails the moment you need it most.
Invest in a purpose built endurance card, match the speed class to your camera's resolution, and replace it on a regular cycle. It is a small cost that protects everything your dash cam is designed to do.
At Borlexa, we carry a curated range of memory cards selected specifically for compatibility and performance with the dash cams we sell.