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SD card size

What size SD card does a 2K (1440p) front and rear dash cam need?

Quick answer

A 128GB card keeps a full 8-hour driving day from a 2K (1440p) front and rear dash cam at a typical 26 Mbps; 32GB covers a 2-hour commute. Buy a high-endurance card and check your camera's maximum supported size.

SANDISK 128GB High Endurance Video microSDXC Card with Adapter for dash cam and home monitoring systems - C10, U3, V30, 4K UHD, Micro SD Card - SDSQQNR-128G-GN6IA

SANDISK 128GB High Endurance Video microSDXC Card with Adapter for dash cam and home monitoring systems -...

128GB / high endurance

The 128GB size that holds a full driving day at this setting, in a high-endurance grade built for loop recording.

How big a card for how many hours?

A 2K (1440p) front and rear camera writes about 11.7GB per hour at a typical 26 Mbps. Each extra 1080p channel adds about 10 Mbps, which is why the rear camera costs you roughly 38 percent of the loop.

Hours to keepSpace neededCard to buy
1 h13 GB16GB
2 h25 GB32GB
4 h50 GB64GB
8 h101 GB128GB
12 h151 GB256GB
24 h302 GB512GB

How long does each card size last at this setting?

CardLoop length
16GB1 h 16 min
32GB2 h 33 min
64GB5 h 5 min
128GB10 h 10 min
256GB20 h 21 min
512GB40 h 42 min

Cards and 2K (1440p) front and rear cameras

Check the camera's maximum supported card size before buying.

Before you rely on this: Windshield-mount rules and audio-recording consent laws vary by state, so check your local law. Researched from published specifications and verified owner reviews, not hands-on testing. General information, not professional advice; check your vehicle manual and your local law.

Frequently asked questions

Is 128GB enough for a 2K (1440p) front and rear dash cam?

128GB holds about 10 h 10 min at this setting. That is more than a full day of driving, so it is plenty for most drivers.

Do I need a high-endurance SD card?

Yes. A dash cam rewrites its whole card every few hours, and ordinary cards are not rated for that. High-endurance cards are built for continuous video and handle windshield heat better. A worn-out card often keeps recording but writes corrupt files, so format it in the camera every few weeks and replace it at the first recording error.

What speed class does a dash cam card need?

Even a three-channel 4K camera writes only a few megabytes per second, so a U3 or V30 card is enough. This setup writes about 3.3 MB per second. Endurance, not speed, is what decides how long a card lasts.

Updated 2026-09-24