Security & surveillance

CCTV Storage Calculator

Plan how much space your CCTV recordings need. Enter your camera count, average bitrate, recording schedule, and retention period to estimate storage in GB and TB—all calculated in your browser.

The storage picture

Your estimate.

A clearer plan for your recordings.

Enter your setup and select Calculate storage to see hourly, daily, and total capacity in GB and TB.

Decimal units: 1 TB = 1,000 GB. Actual usage depends on the recorded bitrate and your recorder’s overhead.

How CCTV storage is calculated

Formula: hourly storage (GB) = cameras × bitrate per camera (Mbps) × 0.45. Daily storage (GB) = hourly storage × recording hours per day. Total storage (GB) = daily storage × retention days. Divide GB by 1,000 for TB.

The factor 0.45 converts megabits per second into gigabytes per recording hour: 1,000,000 bits × 3,600 seconds ÷ 8 bits per byte ÷ 1,000,000,000 bytes per GB. These are decimal GB and TB, not binary GiB and TiB. Hourly storage covers an hour when all cameras are recording, rather than an average across a 24-hour day.

Use the average recorded bitrate shown by your camera or recorder, not its network port speed. The calculator assumes all cameras share the same bitrate and schedule. For mixed bitrates, calculate each group separately and add the unrounded storage requirements.

Resolution, frame rate, scene activity, and H.264/H.265 compression affect the bitrate. They do not need a second multiplier when you already know that bitrate. Variable bitrate and motion-triggered recording make real consumption less predictable; use representative measurements or a conservative bitrate and recording schedule.

The recommended disk capacity adds 20% to the estimated total as an explicit planning allowance, then rounds up to a capacity target of 1 TB or the next even number of TB (2, 4, 6, 8, and so on). This is a ToolVirox planning convention, not a guarantee or a drive-product recommendation. The margin is 20% of the recording estimate, not 20% of the finished disk left free.

Treat the recommended size as usable recording capacity across your disks. It does not calculate RAID redundancy, formatting losses, recorder databases, backups, or extra audio and metadata. Check your recorder’s supported drive sizes, write throughput, and usable space before choosing hardware. A large total may require multiple disks.

Examples

Four cameras recording continuously

Input: 4 cameras × 4 Mbps, 24 hours/day, retained for 30 days.
Result: 7.2 GB/hour (0.0072 TB), 172.8 GB/day (0.1728 TB), 5,184 GB total (5.184 TB). With 20% headroom: 6.2208 TB. Recommended capacity target: 8 TB.

Eight cameras on a daytime schedule

Input: 8 cameras × 2 Mbps, 12 hours/day, retained for 14 days.
Result: 7.2 GB/hour, 86.4 GB/day, 1,209.6 GB total (1.2096 TB). With 20% headroom: 1.45152 TB. Recommended capacity target: 2 TB.

One camera for one week

Input: 1 camera × 1 Mbps, 24 hours/day, retained for 7 days.
Result: 0.45 GB/hour, 10.8 GB/day, 75.6 GB total (0.0756 TB). With 20% headroom: 90.72 GB. Recommended disk-capacity target: 1 TB, the calculator’s minimum sizing tier.

Frequently asked questions

What unit should I use for bitrate?

Enter megabits per second (Mbps), not megabytes per second (MB/s). For decimal kbps, divide by 1,000: 4,000 kbps is 4 Mbps. For MB/s, multiply by 8: 0.5 MB/s is 4 Mbps.

Does this work for H.264 and H.265 cameras?

Yes. Storage follows the bitrate of the recorded stream, regardless of codec. Enter the measured or configured bitrate for your codec; do not apply an additional compression discount.

How do I estimate motion-only recording?

Enter the average number of hours actually recorded per day. For example, recording for roughly half a day corresponds to 12 hours. Activity varies, so the result is only as reliable as that estimate.

Why does my recorder show a different capacity?

Some systems report binary GiB or TiB while labeling them GB or TB. This tool uses decimal units: 1 GB = 1 billion bytes and 1 TB = 1 trillion bytes. Formatting, RAID, and space reserved by the recorder can also reduce usable capacity.

Does the recommendation include RAID or audio?

No. The recommendation adds a general 20% planning allowance, not a RAID calculation. Account separately for redundancy, spare disks, audio, metadata, and other recorder overhead, or include audio in the bitrate you enter if your recorder reports a combined stream rate.

Are my camera details uploaded or saved?

No. The calculation runs in this page in your browser. Inputs are not sent to a server or saved to browser storage, and reset when you reload the page.

Can I use different settings for different cameras?

Calculate each group with a shared bitrate and recording schedule separately. Add the groups’ total storage, apply a suitable overall allowance, and round the final capacity once.

Last reviewed: September 22, 2026