Video calculator
Camera Storage Calculator
CCTV/NVR storage, daily recording rate, retention capacity, and camera network bandwidth.
CCTV and NVR storage planning
Estimate daily GB, retention capacity, usable drive size, and camera network bandwidth.
- Usable capacity needed
- 11.59 TB
- Raw storage
- 10.53 TB
- Daily storage
- 351.13 GB/day
- Total bandwidth
- 32.51 Mbps
- Active hours/day
- 24.0 h
- Per-camera stream
- 4.06 Mbps
Known bitrate mode is the most reliable storage estimate. Add headroom for VBR peaks and drive reserve.
Formula notes
The calculator adds video and audio bitrate per camera, multiplies by camera count, then applies recording hours,
motion duty cycle, and retention days. Storage conversion uses GB = Mbps * seconds / 8 / 1000.
What this calculator is for
Use this camera storage calculator for CCTV, IP camera, NVR, DVR, VMS, and edge recorder planning when you need a practical drive-size estimate before buying disks or sizing a surveillance server.
The network bandwidth result is the instantaneous camera stream load. The storage result is reduced by recording schedule and motion duty cycle because inactive periods do not write full video.
Known bitrate versus resolution estimate
A configured bitrate is better than a resolution guess. Resolution, frame rate, codec, and quality settings help with early planning, but real storage changes with motion, night noise, rain, compression profile, and VBR behavior.
Worked example
Eight cameras at 4 Mbps video plus 64 Kbps audio, recording continuously for
30 days, need about 10.53 TB of raw storage. With 10% reserve overhead, plan
for about 11.59 TB of usable capacity.
Before buying drives
- Use measured camera bitrate when the system is already installed or when vendor profiles are available.
- Set motion duty cycle from real activity, not from a best-case empty-room assumption.
- Add reserve for filesystem overhead, RAID parity, failed sectors, future cameras, and higher quality profiles.
- Confirm whether NVR software reports decimal TB or binary TiB when comparing drive sizes.
Frequently asked questions
How do I calculate CCTV storage from bitrate?
Add video and audio bitrate for one camera, multiply by camera count and active recording hours, then multiply by retention days. Convert megabits to bytes by dividing by 8, and add drive or RAID overhead.
How many days of recording can 1 TB hold?
It depends on camera count, bitrate, recording schedule, and motion duty cycle. A single 4 Mbps stream recording continuously uses about 43 GB per day before audio and overhead, so 1 TB stores roughly 23 days for one camera.
Does motion recording really save storage?
Yes, when the scene is inactive for much of the day. A 30% duty cycle uses about 30% of the continuous-recording storage estimate, but busy entrances, roads, rain, insects, and noise can raise the real percentage.
Should I use H.264 or H.265 for storage planning?
Use the configured or measured bitrate whenever possible. H.265 often needs less bitrate than H.264 for similar scenes, but camera settings, motion, noise reduction, and quality targets matter more than codec name alone.
Why add capacity overhead for NVR drives?
Formatted capacity, filesystem reserve, RAID parity, bad-sector reserve, and operational headroom all reduce usable space. Add overhead so the required drive size is not equal to the raw math result.