Many people have asked how much video can an SD Card hold. This depends on 2 factors: SD Card Size and Bit Rate. You can use our Recording Time Calculator to approximate how much video your SD card can hold. For example, if you have an Itronics ITB-100HD (bit rate is 6Mbps) and a 32GB card, you will get approximately 12.1 hours of video. Note that this is just an approximation since many cameras copy software to the SD card which occupies some space. Also if your camera has a variable bit rate that changes dramatically depending on video conditions, this calculator will not apply. Most dash cams run a very consistent bit rate.
Bit Rate Information
The bit rate is the number of bits processed per unit of time. The lower the bit rate, the more video can be stored on an SD card. Note that higher bit rates can provide better video quality in certain circumstances.
Typically bit rate is calculated in Mbps (usually between 5 and 20) or Kbps ( usually between (5000 and 20,000). Most dash cams have a fixed bit rate but there are some that allow the user to adjust it.
If you want to know what bit rate of a video there are a few ways to find this out. The easiest is just to right click the video, select “Properties” and select the “Details” tab. There should be a “Total bitrate” number.
If you use VLC, you can see the bit rate in the Tools->Media Information->Statistics tab when playing the video. Look for “content bitrate”.
There is also an open source program called MediaInfo, that provides this information as well.
SD Card Information
Most dash cameras support SDHC cards with a maximum size of 32GB. Some new cameras are supporting SDXC cards which have much higher capacities (up to 2048GB).
Last Updated: July 7, 2015