Surveillance Storage Calculator

Estimate how much hard drive storage your CCTV or IP camera system needs with this free Surveillance Storage Calculator. Enter your number of cameras, resolution, frame rate, recording hours, video quality, compression type, and retention period to estimate daily and total storage requirements. Use the results to plan storage for your NVR or DVR system.

How Much Storage Do CCTV Cameras Need?

The amount of storage required for a CCTV system depends on several factors, including the number of cameras, video resolution, frame rate, recording hours, compression type, and how long you want to keep the footage.

A system with a few 1080p cameras may need only a few terabytes of storage, while a larger installation with 4K cameras recording around the clock can require several dozen terabytes or more.

Our Surveillance Storage Calculator helps you estimate your requirements before choosing a hard drive for your NVR or DVR. The result is a planning estimate, so actual storage use may vary depending on your cameras and recording settings.

How to Use the Surveillance Storage Calculator

Follow these steps to estimate your CCTV storage requirements:

Enter the number of cameras: Include every camera that will record footage.
Choose the frame rate: Select the frames per second (FPS) used by your cameras.
Set recording hours: Enter how many hours each camera records per day, from 1 to 24.
Select retention days: Choose how many days you want to keep recorded footage.
Choose the resolution: Select 960H, 720p, 1080p, 3MP, 5MP, or 8MP/4K.
Select video quality: Choose low, medium, or high.
Choose the compression type: Select M-JPEG, H.264, or H.265.

The calculator updates automatically as you change the settings. You can review the estimated total storage, daily storage usage, per-camera storage, and estimated bitrate in the results panel.

Surveillance Storage Calculation Examples

Here are two examples to help you understand how storage requirements can change with different camera setups.

Example 1: 12 Cameras at 1080p

Suppose you have 12 cameras recording at 1080p and 15 FPS. You use H.264 compression, medium video quality, and record for 12 hours each day. You want to retain footage for 15 days.

Using the calculator’s estimated bitrate of 4 Mbps per camera:

Number of cameras: 12
Recording time: 12 hours per day
Retention period: 15 days
Estimated daily storage: 259.2 GB
Estimated total storage: 3.888 TB

You would need more than the calculated amount in practical use if you want room for overhead, changing recording conditions, and future expansion.

Example 2: 8 Cameras at 4K Resolution

Suppose you have eight 4K cameras recording at 15 FPS, using H.264 compression and medium video quality. Each camera records continuously for 24 hours per day, and you want to keep footage for 30 days.

Using the calculator’s estimated bitrate of 12 Mbps per camera:

Number of cameras: 8
Recording time: 24 hours per day
Retention period: 30 days
Estimated daily storage: 1,036.8 GB
Estimated total storage: 31.104 TB

This example shows why high-resolution cameras and continuous recording can require significantly more storage.

These examples use the calculator’s built-in bitrate assumptions. Actual results can differ from the storage consumption reported by your cameras or recorder.

Surveillance Storage Calculation Formula

The calculator estimates storage using the following formula:

Daily storage (GB) = Bitrate (Mbps) × Recording hours × 0.45 × Number of cameras

Total storage (GB) = Daily storage (GB) × Retention days

The factor 0.45 converts megabits per second into an approximate number of decimal gigabytes per recording hour.

For example, a camera recording at an estimated 4 Mbps for 12 hours uses approximately:

4 × 12 × 0.45 = 21.6 GB per day.

For 12 cameras recording for 15 days, the estimated requirement is:

21.6 × 12 × 15 = 3,888 GB, or 3.888 TB.

These calculations are estimates based on the selected settings and assumed bitrate, not a guarantee of actual disk usage.

What Affects CCTV Storage Requirements?

Several factors determine how much hard drive capacity your surveillance system needs.

Camera resolution: Higher resolutions, such as 4K, can require more storage because they capture more image detail.
Frame rate: Higher FPS settings generally increase storage requirements when other settings remain unchanged.
Compression: H.264 and H.265 compress video efficiently. H.265 can often provide similar visual quality at a lower bitrate, depending on the camera and settings.
Video quality and bitrate: Higher bitrates generally produce larger recordings.
Recording schedule: Continuous recording usually needs more storage than motion-triggered recording when the latter records for fewer hours.
Retention period: Keeping footage for 30 days requires more storage than keeping it for seven days under otherwise identical conditions.

How to Choose a Hard Drive for CCTV

Once you have estimated your storage requirements, choose a suitable hard drive for your recorder. Surveillance-rated drives are designed for the continuous workloads commonly found in CCTV systems.

Allow additional capacity beyond the calculated estimate. Also check the maximum supported drive capacity, number of drive bays, RAID configuration, and compatibility of your NVR or DVR before purchasing storage.

Remember that a hard drive’s advertised capacity and the capacity available for recordings may differ. If footage must be retained for legal, business, or security reasons, verify the required retention period and test your actual recording setup.

Frequently Asked Questions

1. How much storage do 4 CCTV cameras need?

It depends on the resolution, bitrate, recording hours, compression, and retention period. Four cameras recording at 1080p may need much less storage than four 4K cameras recording continuously. Enter your settings in the calculator for an estimate.

2. How much storage do 16 CCTV cameras need for 30 days?

There is no single storage requirement for every 16-camera system. A system using low bitrates and motion-triggered recording can need considerably less space than a high-resolution system recording 24 hours a day. Select 16 cameras and 30 retention days in the calculator, then adjust the other settings to match your installation.

3. Is H.265 better than H.264 for CCTV storage?

H.265 can reduce storage and bandwidth requirements compared with H.264 at similar visual quality. The actual savings depend on the camera, bitrate, scene activity, and encoding settings. Check that your recorder supports H.265 before selecting it.

4. Does a higher frame rate use more storage?

Generally, yes. Higher frame rates capture more frames per second and can increase the bitrate required to maintain similar image quality. The actual increase depends on the encoder and recording settings.

5. How many days can a 2 TB hard drive record CCTV footage?

The answer depends on the combined bitrate of all cameras and how many hours they record daily. A 2 TB drive may retain footage for many days in a low-bitrate setup but considerably fewer days with multiple high-resolution cameras. Use the calculator to estimate the storage needed for your target retention period.

6. Does motion detection reduce CCTV storage?

It can. Motion-triggered recording stores less footage when cameras spend substantial time recording no activity. The savings depend on how frequently motion occurs, recording duration before and after detection, and whether the system records continuously on selected channels.

7. Should I buy a hard drive with exactly the calculated capacity?

It is better to allow extra capacity. Actual bitrates can fluctuate, and the usable capacity may be lower than the advertised capacity. Check your recorder’s compatibility and consider future camera additions before choosing a drive.

8. Is this Surveillance Storage Calculator accurate?

The calculator provides an estimate based on assumed bitrates for the selected resolution, quality, frame rate, and compression type. Actual storage consumption varies by camera model, scene movement, lighting, variable-bitrate encoding, audio, and recording schedule. For a precise installation plan, compare the estimate with your camera or recorder’s actual bitrate measurements.