DVR Recording Time: What Is The Best HD For My Project?

When we decide to mount a CCTV system (Closed Circuit or Internal Television) , we need to be aware of all the details.

As important as the transmission quality, it is the recording time that your DVR will store data.

The CCTV (camera) devices provide videos in a specific format and send them to a DVR or NVR recorder that will allow the videos to be stored according to the configuration set by the technician who installed the device.

However, with planning still in progress, the contractor will have to do a calculation of how much DVR recording time will need to be maintained.

Everything will depend on the image quality, quantity of cameras, storage capacity of your HD, etc.

By default, when we set up a project, it is usually scheduled for recording to be stored for 30 days.

After this period, the HD will subscribe.

In this case, if the event happened 45 days ago, it will not be possible to reacquire the recording of the video.

This number (30 days) is only exceeded in private cases, that is, for Government projects that increase the days of recording from 30 to 90 days, and this ends up requiring even more storage space on the DVR / NVR.

It is very important to estimate a video recording and retention time since the number of hard disks (HD) will require calculations that involved several factors.

Dvr Recording Time: Calculating Factors

Let’s understand in a simplified way, what elements are essential to make the recording time calculation of a DVR device.


There are some important factors that you need to know about storage space such as Resolution.

We all like to watch videos in high resolution and when we think of security, we need to have all the little details at hand.

But you have to keep in mind that the higher the resolution of recording, the greater the utility of storage space.

If we set the recording to FullHD the use of the HD will go up and this could compromise the video reading, further reducing the HD capacity.

Square Rate Per Minute  (Frame Rate)

Another important factor is the Frame Rate.

That is, the measure of the number of individual pictures or frames that a given optical or electronic device processes and displays per unit of time.

Real-time activities usually require more frame rate per second, however, if we adjust the system setting to 30 fps it will require more storage space.

Generally the default in most cases is the use of 15 fps.

CODEC (Compaction Algorithm)

Making the correct choice of CODEC will greatly influence the amount of hard disk required for recording.

More up-to-date algorithms like H.264 and H.265 can give you more security and still save a lot of space on your recording.

Scenery Movement

If the scene where the camera was inserted gives you great movement of people and objects, know that the space for storage will increase.

By always having enough movement, the camera will record several images and consequently will occupy more space on your hard disk.

Constant Recording By Event

Generally when setting up a DVR, we have two options available:

Whether videos will be stored constantly, that is, even when an event is not in place, or whether the recording will be performed when recording an event when it notices a movement.

Choosing the option to record only when a movement is recorded will make you lose space with things considered “useless”.

Extra Tip

Intelbras has separated a table that can serve as a basis for you to use when in doubt as to what is the best HD for your CCTV project.

You have the size of the HD, the resolutions available and how many days on average, this HD would support recording the chosen amount of cameras.

Part of the table, with the most wanted HD: 1 TB and 2 TB.


On smaller projects, it is common for users to be dissatisfied with the recording time, because “dvr does not record everything” and this happens due to lack of storage capacity.

It is important to look at the table with the recording time of each HD to DVR and choose an ideal one for your recording need.

You can even spend a little more on a bigger HD, but it will ensure you have everything stored correctly.