How Long Do Security Cameras Record: Easy Formula to Calculate & Top Things to Know

" How long do security cameras record " is one of the most frequently asked questions you might have, when you are about to buy a security camera system, or just curious about the recording period of the CCTV cameras installed in the public.

You can check the easy formula below to see whether the storage space of a security camera or system can meet your requirements, and get the important points and answers to hottest questions on "How far back can CCTV cameras go".

How Long Do Home & Business Security Camera Record: The Detailed Formula for You

When you need to calculate how many days or hours a security camera can record, you should check the below variables that determine the CCTV camera recording time first:

• Resolution: The higher the resolution is, the shorter time the security cameras will record.

• Compression: Video compression reduces the size of the original video and offers longer security camera recording time.

• Bitrate: Higher bitrate will provide shorter recording period of a CCTV camera.

• The number of cameras: More cameras will require more storage space, thus reduce the video recording time.

• The storage space: Larger storage space usually provides longer CCTV camera footage recording time.

Through our team's detailed tests, we summarized the below formula to help you calculate how long security cameras can record, thus you can confirm whether a security camera or system with onboard storage space can meet your requirement for video storage.

For Recording Videos in HDD of NVR/DVR Security Camera System:

Recording Days = (Storage Space (GB) * 1024²* 8)/ (Bitrate (kb/s) * 3600 * 24 * Cameras)

For Recording Videos in SD Card of a Standalone IP Camera:

Recording Hours = Storage Space (GB) * 1024² * 8/Bitrate (kb/s)/3600

Let's take Reolink RLK8-800B4 security camera system (with 4 cameras and a built-in 2 TB HDD in the NVR), and RLC-410W standalone IP camera with an SD card slot as examples to show you how long surveillance cameras can record, and how long you can record with 1 TB.
Reolink RLK8-800B4 security system basics:

• 2 TB HDD for video recording = 2048 GB
• 4 PoE IP cameras
• The bitrate for IP cameras: 8192 kb/s (for 8MP high definition)

Take the variables into the formula, and you can see how long the security camera system can record.

Recording Days = (Storage Space (GB) * 1024 ² * 8)/ (Bitrate (kb/s) * 3600 * 24 * Cameras)
Recording Days = (2048 GB * 1024 ² * 8)/(8192 (kb/s) * 3600 * 24 * 4) = 6 Days

You can also check the CCTV camera storage consumption formula here>>

It means that with the 2 TB built-in HDD in the NVR, the system can support 4 cameras doing 24/7 recording in 8MP Super HD for 6 days.

If you have the same questions as OPs on forums, who asked "How long does the average security camera store footage, or how long is security camera footage kept", hope you've got the answer here.

If you want to extend the recording time of this CCTV security camera system, you can lower the bitrate of the video recording streaming, or try motion detection recording, which will start recording footages only when there are motion events.

If you stick to recording continuous videos in high definition, you can install an external hard disk drive via e-SATA for more storage space and longer recording time (up to 12TB with maximum 4TB HDD/port).

You can review the footages and back up the important data you want before the videos gets overwritten once the storage space is full.

Reolink RLC-410W standalone IP camera basics:

• Comes with the SD card slot. Assume we insert a 32GB SD card to this camera
• The bitrate of this camera: 8192 kb/s (for 5MP Super HD)

Put the variables into the formula, and you can see how far back this security camera can record in 5MP Super HD.
Recording Hours = Storage Space (GB) * 1024 ² * 8/Bitrate (kb/s)/3600
Recording Hours = 32 (GB) * 1024 ² * 8/8192 (kb/s)/3600 = 9 Hours

Please note that RLC-410W standalone IP camera can only support motion detection recording, when there are no other video storage options, which means that this camera will start recording footage only when there are motion-triggered events.

Based on our team's tests, this WiFi IP security camera can record and save up to 400 motion events in the 32 GB SD card for your later playback.

You can back up the recording footage you want before it gets erased once the SD card storage space is about to run out.

Some of you may ask, "How often do CCTV cameras overwrite materials". The security cameras & systems will automatically overwrite the oldest video footage once the storage space runs out.

Now you can confirm whether a security camera or system can satisfy your video recording period requirements. But wait. Enough recording period doesn't mean that you can capture what you want when playing back the recorded videos.

You also need to check the below important points when you buy a security camera & system with enough recording storage space.

Important Point 1. Make Sure Your Security Cameras Can Capture the Details You Want

Now assume that you are reviewing the recording videos captured by your security cameras, but you can only see blurry footage without any details you want (such as license plates, peoples' faces).

The result is that no matter how far back CCTV footages go, you won't record what you want.

So in order to capture what you really want, like license plates or faces from a certain distance, you need at least 2MP Full HD security cameras, or 4MP and even 5MP CCTV cameras with optical zoom function (for identifying details of far-away objects).

You can check this post that explains why a 1080p security camera can read license plates and human faces.

Also take RLC-811A as an example. Its 8MP high definition and 5X optical zoom enable you to record all the details you want. So you won't miss the important details in your recorded videos.

You can watch the below clear video captured by RLC-811A security camera (shared by a real user).

Clear security camera videos are extremely important for case investigation should any crimes happen (such as car vandalism, harassment, etc.). That's one of the most important reasons why you need to ensure that your security cameras can record the details.

An OP posted a post on Reddit, stating below:
Currently, we've got one analog DVR camera set. They work fine for very general surveillance, but provide nothing actionable for the police (can't see faces, license plates).
We want to get a small handful of cameras for entrances/exits/driveways that will be able to capture high quality detail like license plates and faces (beyond a blob).

So better go for a high definition IP camera or system, especially with optical zoom (for identifying far-away details), when you need to record the CCTV camera footages.

Important Point 2. Make Sure There Is No Video Loss When Recording Security Camera Footage

Video loss is really traumatic, especially for the most important video clips.

If a home break-in or car theft happens, and your security cameras fail to capture such events, what's the point of video recordings?

So make sure your security cameras have no video loss or recording delay issue, especially for motion detection recording.

Take Reolink security cameras as typically examples. The cameras support pre-record (3s – 5s) and post-record (15s – 1min, based on your personal settings) functions, which will start recording before the motion event happens, and will keep recording after the motion event has ended.

When you are playing back the motion detection recordings, you will see the complete motion event instead of just an occurent action. You can see before the object triggered the motion and after it has ended.

When wandering around forums, we noticed that some of you are curious about how many days or how long CCTV surveillance security cameras can record in the public.

So we decide to write down the hottest questions you may have about public security camera recording and add the detail answers below the question list.

• How long does Walmart keep security camera footage?

• How long do retail stores keep surveillance videos?

• How long does Target keep surveillance footage?

• How long do banks keep video surveillance?

• How long does McDonalds keep security footage?

• How long do grocery stores keep surveillance tapes?

• How long do schools keep security footage?

• How long do gas station security cameras record?

• How long do hotels keep video surveillance tapes?

• How long does Macy's keep security footage?

There is no standard length of time that video surveillance recording must be kept in the hotel, bank, supermarket, stores, shopping malls, etc.

On average, the security camera footage will be stored about 30 – 90 days in hotels, stores or supermarkets, and the above places, etc.

Banks generally keep ATM security camera videos for 6 months in accordance with the banking industry standard. But it may also vary among different banks and the countries you are in.

And some regulations would require that the recordings of the casino security cameras need to be kept for 6 months or 1 year.

If you want to know about how long video surveillance cameras can record in other public places, please leave them in the comment below. We will reply to you ASAP!

Also we've summed up the frequently asked questions about "Security Cameras Record". You can learn more about the security camera video recording in the coming part.

"Security Cameras Record" Hottest Questions & Quick Answers

We always try to answer all the questions you may have on security camera recordings, so we make this specific part here.

If you have other questions, please leave them in the comment below. We will add your questions in this list.

Q 1: How to Get Security Camera Footage from a Store, Supermarket, etc.?

Can you ask to see CCTV footage? How long does it take to get surveillance videos?
A 1: You have the rights to request CCTV footage that relates to you and your property.

And you can request security camera video recordings from private individuals, companies, and public authorities. Please note that the footage is needed for crime investigation, or you suspect the camera is being used for harassment and other illegal purposes. Under such circumstances, this can only be handled by the police.

You need to make a request to the owner of the security cameras if you want to check the footage. The below information is needed when sending the request:

• A specific date and a time
• Proof of your identity
• A description of yourself

You may need to pay about £10 for the video recording footage.

Q 2: How Often Do Stores Check Their Cameras?

Do shops check their CCTV footage for shoplifters, or just check at the moment and never after? Are security cameras in stores and shops always on?
A 2: Typically the security cameras in stores, shops and other public places are always on for 24/7 video surveillance, in case that anything unusual would happen.

Some stores would check the security camera videos before the footage is cleared because of running out of capacity. And they might import the footage for data backup.

Some shops may check security camera footage every day to see whether there are any shopliftings or crimes.

Q 3: Do Security Cameras Record All the Time?

A 3: Basically, there are 3 types of security camera video recording methods:

• 24/7 video recording
• Schedule recording: You can record the videos based on your own setting.
• Motion detection recording: Your security cameras will start recording only when there are motion events.

Whether security cameras record all the time or not is determined by personal settings.

Q 4: How Do I Store Footage of My Security Camera Without DVR/NVR?

Do you need hard drive for security cameras recording?
A 4: You can still get surveillance cameras recording footage even without DVR or NVR.

If you want to get continuous recording on your security cameras without DVR, you can record the videos to your computer (you need to keep the security camera client running all the time on your PC), or try uploading the footage to the FTP server, or cloud.

You can also store motion-triggered videos in the SD card of the standalone security cameras.

For more details, please check this post to see more recording security camera videos with or without DVR/NVR.

Q 5: Can I Record Security Camera Videos Without Internet?

A 5: Yes, you can still get video recording even without Internet access.

For example, the cameras and the NVR of the RLK8-800B4 system (mentioned above) communicate with their proprietary network. The videos captured by the security cameras will be recorded to the HDD of the NVR once power them on.

And security cameras with SD card will record the motion events to the memory card even without WiFi or Internet, so you won't miss important events.

The security cameras will only use the Internet when you view live streaming or when the cameras send push notifications to you.

The video recordings won't take up the Internet bandwidth. You can get more details on CCTV cameras without Internet here.

You are invited to add more questions to the list!