CCTV Bandwidth Requirements Calculator
Calculate the total network bandwidth and daily storage requirements for your CCTV surveillance system based on resolution, frame rate, compression, and number of cameras.
Formulas Used
1. Raw bitrate per camera (bps)
RawBitrate = (MP × 1,000,000) × 3 × BitDepth × FPS
2. Compressed bitrate per camera (bps)
CompressedBitrate = RawBitrate × CompressionFactor
3. Total bandwidth with overhead (Mbps)
TotalBW = (CompressedBitrate / 1,000,000) × Cameras × (1 + Overhead/100)
4. Storage per camera per day (GiB)
Storage = (CompressedBitrate × RecordingHours × 3600) / (8 × 2³⁰)
5. Total storage (TiB)
TotalStorage = StoragePerCamPerDay × Cameras × RetentionDays / 1024
Assumptions & References
- Raw frame size assumes RGB colour space with 3 channels (Y, Cb, Cr or R, G, B).
- Compression factors are industry-typical averages: H.264 ≈ 0.15, H.265 ≈ 0.08, H.265+ ≈ 0.05 relative to uncompressed video (SMPTE / Hikvision white papers).
- Network overhead (default 20%) accounts for TCP/IP packet headers, retransmissions, and protocol encapsulation per IEEE 802.3 Ethernet framing guidelines.
- Storage uses binary GiB/TiB (1 GiB = 2³⁰ bytes) consistent with hard-drive manufacturer specifications.
- A 10% file-system overhead is added to the recommended NVR storage to account for NTFS/ext4 metadata and fragmentation.
- Motion-based recording, variable bit rate (VBR), and scene complexity are not modelled; real-world bitrates may be 30–50% lower with VBR.
- References: ONVIF Profile S specification; IEC 62676-1-1 (CCTV systems); Axis Communications bandwidth calculator methodology.