IP Camera Storage Calculator - Bandwidth & NVR Disks
Size IP camera bandwidth, 24/7 or motion recording, retention and NVR disks from measured bitrate.
Disks and link (optional)
Sizing result
Formulas and assumptions
- Average/peak ingress (Mbps) = cameras × (video bitrate + audio bitrate ÷ 1,000). Compare peak ingress with the relevant physical link, not Internet speed unless video really crosses it.
- GB/day = average ingress (Mbps) ÷ 8 × recording hours/day × 3.6 × recorded-time fraction. Footage TB = GB/day × days ÷ 1,000. Planned nominal TB = footage TB ÷ (1 − free-space reserve).
- Disks needed = round up (planned nominal TB ÷ TB per disk). Retention with installed disks = available nominal TB × (1 − reserve) ÷ daily TB. This does not subtract RAID parity or replication.
Network ingress assumes the cameras send their primary streams continuously to the recorder. Motion recording reduces stored footage here, not this link load. Extra live-view and remote streams are excluded.
TB and GB use decimal units (1 TB = 1,000 GB). Disk reserve is free space, not RAID redundancy. Actual formatted capacity, filesystems, metadata, VBR peaks and failures can reduce retention.
Use a measured or manufacturer-estimated bitrate for your exact camera, codec, scene, frame rate and audio. Resolution alone does not determine storage or bandwidth.
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How to size an IP camera network and NVR storage
- Enter camera count and an average and peak video bitrate per camera. Use actual NVR/camera settings or a vendor estimate; set audio to zero if unused.
- Set recording hours, the share of that window actually stored, retention days and free-space reserve. Continuous recording uses 100% of the window.
- Optionally enter disk size, number already installed, disk price and the camera-to-NVR link capacity. The result separates simultaneous network ingress from bytes stored per day and shows a disk count and estimated retention.
- Review the formulas and limits below the result. Motion-only recording does not necessarily stop the camera stream on the network; RAID, live viewing and protocol overhead require separate planning.
NVR sizing questions
Can I choose bitrate from resolution alone?
No. Codec, frame rate, scene motion, light and encoder settings all affect bitrate. Measure it or use the camera manufacturer's estimate.
Why is network traffic unchanged when I reduce recorded time?
This model assumes continuous camera-to-NVR transport with selective recording. Some event-only architectures transport differently; measure their traffic separately.
Is this a RAID or fault-tolerance calculator?
No. Disk count is a capacity-only estimate. Subtract parity, mirrors, hot spares and other overhead separately before buying hardware.