Recording Storage Calculator
Work out how much storage continuous recording needs. Enter a bitrate, how many hours per day you record and over how many days — the calculator returns the total in GB or TB. Built for security camera retention planning, long screen captures, dashcams, podcasts and raw audio sessions.
Last reviewed on August 26, 2026
Recording Settings
Storage Required
Recording Time Per Drive
At Other Bitrates (per day, all channels)
How Recording Storage is Calculated
The formula
GB = Bitrate (Mbps) × 3,600 × Hours ÷ 8 ÷ 1,024
Example: 2 Mbps × 3,600 × 24 ÷ 8 ÷ 1,024 = 21.1 GB per day
Bitrate is measured in bits per second, storage in bytes, so the divide by eight is what converts one into the other. Everything else is duration. Multiply by the number of cameras, then by the retention period in days, and you have the array size you need to buy.
Note that this is recorded bitrate, not the sensor resolution. A 4K camera set to 4 Mbps writes exactly as much data per hour as a 1080p camera set to 4 Mbps — it just looks worse doing it.
H.264 versus H.265 (HEVC)
The codec does not change the arithmetic above. What it changes is the bitrate you need for a given picture quality. H.265 delivers roughly the same quality at about half the bitrate of H.264, so a camera you would have run at 4 Mbps on H.264 can often sit at 2 Mbps on H.265 with no visible loss. Halve the bitrate in the calculator, not the result.
Older network video recorders and some browsers cannot decode H.265, so check playback compatibility before committing an entire installation to it.
Constant versus variable bitrate
Constant bitrate (CBR) writes the same amount of data every second regardless of what is in frame, which makes storage planning exact — the figure above is the figure you get. Variable bitrate (VBR) spends more on movement and less on static scenes, typically landing 20 to 40 percent below the CBR figure for a fixed camera pointed at an empty corridor, but spiking well above it during busy periods.
For retention guarantees, size the array using CBR maths. For a rough estimate on a quiet scene, apply one of the motion-detection percentages in the calculator.
Storage Per Bitrate: Quick Reference
Video recording
| Bitrate | Typical source | Per hour | Per 24 hours | 30 days continuous |
|---|---|---|---|---|
| 1 Mbps | 720p security camera | 0.44 GB | 10.5 GB | 316 GB |
| 2 Mbps | 1080p security camera | 0.88 GB | 21.1 GB | 633 GB |
| 4 Mbps | 1080p, higher quality | 1.76 GB | 42.2 GB | 1.24 TB |
| 5 Mbps | 4K H.265 camera | 2.20 GB | 52.8 GB | 1.55 TB |
| 8 Mbps | 1080p 30fps screen capture | 3.52 GB | 84.4 GB | 2.47 TB |
| 16 Mbps | 1080p 60fps phone video | 7.03 GB | 169 GB | 4.94 TB |
| 50 Mbps | 4K 60fps phone video | 21.97 GB | 527 GB | 15.45 TB |
| 120 Mbps | 4K 120fps, high quality | 52.73 GB | 1.24 TB | 37.1 TB |
Audio recording
| Format | Bitrate | Per minute | Per hour | Hours in 5 GB |
|---|---|---|---|---|
| MP3, 128 kbps | 128 kbps | 0.94 MB | 56.2 MB | ~91 hours |
| MP3, 320 kbps | 320 kbps | 2.34 MB | 141 MB | ~36.4 hours |
| AAC, 256 kbps | 256 kbps | 1.88 MB | 113 MB | ~45.5 hours |
| FLAC, CD source | ~800 kbps | 5.86 MB | 352 MB | ~14.6 hours |
| WAV, 44.1 kHz 16-bit | 1,411 kbps | 10.33 MB | 620 MB | ~8.3 hours |
| WAV, 48 kHz 24-bit | 2,304 kbps | 16.88 MB | 1,013 MB | ~5.1 hours |
| WAV, 96 kHz 24-bit | 4,608 kbps | 33.75 MB | 1.98 GB | ~2.5 hours |
| WAV, 192 kHz 24-bit | 9,216 kbps | 67.50 MB | 3.96 GB | ~1.3 hours |
All figures are stereo. Mono halves them; each extra channel adds proportionally. The audio file size calculator handles arbitrary sample rates and bit depths.
Common Recording Scenarios
4-camera CCTV, 30 days
1080p at 2 Mbps, continuous
~2.5 TB
One hour of 1080p footage
30fps at 2 Mbps
~0.88 GB
Podcast session
2 hours, WAV 44.1 kHz 16-bit
~1.2 GB
30 min 1080p 60fps clip
Phone footage at 16 Mbps
~3.5 GB
Frequently Asked Questions
How much storage does a security camera use per day?
One 1080p camera recording continuously at 2 Mbps writes about 21.1 GB per day, or roughly 633 GB over 30 days. At 4 Mbps that doubles to 42.2 GB per day. Motion-only recording typically cuts the total by 60 to 80 percent, depending on how busy the scene is.
How much memory does 5 Mbps H.265 need per day?
5 Mbps continuous produces 52.8 GB per day and about 1.55 TB over 30 days. The codec does not alter that calculation — H.265 helps by letting you set a lower bitrate for the same picture quality, usually around half what H.264 requires.
How long do you have to record to reach 5 GB in WAV?
Stereo CD-quality WAV at 44.1 kHz and 16-bit runs at 1,411 kbps, about 10.33 MB per minute, so 5 GB is roughly 8 hours 15 minutes. At 96 kHz and 24-bit the rate climbs to 4,608 kbps and 5 GB lasts about 2 hours 32 minutes.
How many GB is a 30 minute 1080p 60fps clip?
About 3.5 GB at a typical 16 Mbps. Phone footage recorded at 20 Mbps comes to roughly 4.4 GB, while a compressed 8 Mbps stream is about 1.8 GB. Frame rate matters only through the bitrate the encoder chooses.
How much storage for 1.5 Mbps recorded 24 hours a day for 30 days?
About 15.8 GB per day and roughly 475 GB over 30 days for a single channel. Multiply by the number of cameras: four channels at that bitrate need about 1.86 TB, which fits on a 2 TB drive with almost no headroom — size up to 3 TB if you want the full retention window guaranteed.
Does frame rate change how much storage I need?
Only indirectly. Storage is determined by bitrate alone. Raising the frame rate makes the encoder need a higher bitrate to hold the same quality, so it increases storage in practice — but if you cap the bitrate, a 60fps stream and a 30fps stream occupy identical space and the 60fps one simply looks softer.