Bandwidth Calculator
Estimate the bandwidth required for video streams and simultaneous connections.
Enter Your Bandwidth Requirements
Table of Contents
Complete Bandwidth Guide
What is Bandwidth?
Bandwidth refers to the maximum amount of data that can be transmitted over a network connection in a given period of time. It is typically measured in bits per second (bps), with common units being Mbps (megabits per second) or Gbps (gigabits per second). When multiple users or streams share the same connection, each consumes a portion of the available bandwidth.
Why Calculate Bandwidth?
Knowing your bandwidth requirements helps you:
- Choose the right internet plan for your needs
- Size infrastructure for video conferencing or streaming services
- Plan surveillance systems with multiple cameras
- Avoid network congestion and quality degradation
The Calculation Formula
Total Bandwidth = Number of Streams × Bitrate per Stream
Example: 10 HD streams at 5 Mbps each = 50 Mbps minimum required.
Upload vs Download: Asymmetric Connections
Most home and business connections are asymmetric: download speed is typically 5-10x higher than upload. For video conferencing, live streaming, or running a server, upload bandwidth is the bottleneck. A 100 Mbps connection might offer only 20 Mbps upload - enough for 4-6 HD streams outbound but insufficient for a small streaming operation.
Bitrate Reference by Quality
Video bitrate varies significantly based on resolution, codec, and compression. Here are typical values:
| Quality | Resolution | Typical Bitrate | Use Case |
|---|---|---|---|
| SD | 480p | 1-2 Mbps | Basic video calls, legacy systems |
| HD 720p | 1280×720 | 3-5 Mbps | Video conferencing, streaming |
| HD 1080p | 1920×1080 | 5-8 Mbps | Full HD streaming, surveillance |
| 4K | 3840×2160 | 15-25 Mbps | 4K streaming, high-end surveillance |
Note: H.264/H.265 codecs can reduce bitrate by 30-50% compared to older codecs at the same quality.
Use Cases and Applications
Video Conferencing
Zoom/Teams/Meet: ~2-3 Mbps per participant in HD. For 20 participants: plan 50-60 Mbps upload. Group calls use selective forwarding (SFU) so your upload = your outgoing stream only, not the sum of all participants.
Recommendation: 4 Mbps upload minimum per active camera for HD quality.
IP Surveillance
Each 1080p camera: 4-8 Mbps with H.264, 2-4 Mbps with H.265. 10 cameras = 40-80 Mbps (H.264) or 20-40 Mbps (H.265). Motion detection and variable bitrate can reduce average by 30-50%.
Storage: 1 TB holds ~7-14 days of 1080p continuous recording per camera.
Streaming Platform
Transcoding to multiple qualities: sum of all output bitrates. 1000 concurrent viewers at 5 Mbps each = 5 Gbps egress from your CDN. Use adaptive bitrate (ABR) - users average 2-4 Mbps, reducing total load.
CDN cost scales with egress bandwidth delivered.
Gaming / Remote Desktop
Cloud gaming (Stadia, GeForce Now, Xbox Cloud): 15-35 Mbps for 4K, 10-25 Mbps for 1080p. Latency matters more than raw bandwidth. Remote desktop (RDP, VNC, Parsec): 2-10 Mbps depending on resolution and refresh rate.
Competitive gaming: 5 Mbps is usually sufficient; <50ms latency is critical.
Other Use Cases
- VoIP: 0.1 Mbps per call (G.711) to 0.15 Mbps (wideband)
- File sync (Dropbox, OneDrive): limited by your upload; large initial sync can saturate connection for hours
- Smart home / IoT: negligible per device (typically <0.01 Mbps), but 50+ devices add up
Network Overhead and Best Practices
Always add overhead to your calculated bandwidth. Real-world factors that increase requirements:
- TCP/IP headers: 5-10% overhead (each packet has ~40 bytes of headers)
- Retransmissions: 5-15% for packet loss on unstable networks
- Peak usage: traffic bursts can exceed averages by 20-50% (concurrent users don't all stream at once)
- Encryption (TLS/SSL): adds ~1-2% overhead but mainly impacts latency
- Quality fluctuations: VBR (Variable Bitrate) streams can spike during complex scenes
Video Codecs and Compression
The video codec used has a major impact on bandwidth. Modern codecs achieve the same visual quality at significantly lower bitrates:
- H.264/AVC: Most common. 1080p typically needs 5-8 Mbps for good quality.
- H.265/HEVC: 30-50% smaller than H.264 at same quality. 1080p at 2.5-4 Mbps.
- AV1: Open, 20-30% better than HEVC. Growing support (YouTube, Netflix).
- VP9: Google's codec, similar to H.265. Used by YouTube.
When choosing equipment (cameras, encoders), prefer H.265/HEVC for bandwidth savings. Ensure your network and playback devices support the codec.
Bits vs Bytes: Understanding Units
Network speeds are in bits per second (bps), while file sizes are in bytes. 1 byte = 8 bits. A 100 MB file = 800 Mb (megabits). At 100 Mbps, download time = 800 Mb ÷ 100 Mbps = 8 seconds.
Quick conversion:
Mbps (network) ÷ 8 = MB/s (download speed in megabytes per second)
Example: 100 Mbps ≈ 12.5 MB/s download speed