Bandwidth Calculator
Convert between bits and bytes, size a connection for concurrent users, and estimate monthly data transfer.
Your details
Usage
Monthly transfer
This calculator runs entirely on your device. Nothing you enter is uploaded, stored, or sold. How this works
Sufficient bandwidth
240.0 Mbps needed
500 Mbps available leaves 260.0 Mbps of headroom (48% utilized)
Includes your inputs, the full breakdown, and every row of the table.
Download speed
62.5 MB/s
500 Mbps ÷ 8
Max concurrent users
52
At 8.0 Mbps each
Monthly transfer
21,600 GB
8.0 h/day at 40% utilization
Per-user allocation
20.0 Mbps
- Connection speed
- 500.00 Mbps
- In bytes per second
- 62.50 MB/s
- Raw demand (25 × 8.0 Mbps)
- 200.0 Mbps
- Protocol overhead (20%)
- 40.0 Mbps
- Total required
- 240.0 Mbps
- Headroom
- 260.0 Mbps
| Activity | Bandwidth per stream |
|---|---|
| Voice call / VoIP | 0.1 Mbps |
| Standard video call | 1.5 Mbps |
| HD video conference | 3 Mbps |
| SD video streaming | 3 Mbps |
| HD (1080p) streaming | 5 Mbps |
| 4K streaming | 25 Mbps |
| Cloud backup / large file sync | 20+ Mbps |
| Online gaming | 3 Mbps + low latency |
What this means
- Marketing speeds are in megabits, file sizes are in megabytes. Divide by eight to convert — a 500 Mbps connection downloads at about 62.5 MB per second at best.
- Add fifteen to twenty-five percent for protocol overhead. TCP/IP headers, retransmissions, and encryption all consume real capacity.
- Upload capacity matters more than most people expect for video calls, cloud backup, and hosting. Asymmetric connections often bottleneck on the upstream side first.
How the bandwidth calculation works
Bandwidth planning has two halves: converting the units correctly, and adding enough overhead. Bits versus bytes is a factor of eight and is the single most common source of confusion — a 100 Mbps link transfers about 12.5 MB per second, not 100.
For a shared connection, multiply concurrent users by their typical per-user demand, then add fifteen to twenty-five percent for protocol overhead and burstiness. Sizing to exactly the average demand guarantees congestion at peak.
Frequently asked questions
How much bandwidth do I need per user?
Roughly 5-10 Mbps for general office work with video calls, 25 Mbps if 4K streaming is expected, and under 1 Mbps for voice and basic web use.
Why is my download slower than my rated speed?
Speeds are advertised in megabits and file managers report megabytes — divide by eight. Beyond that, protocol overhead, server limits, and Wi-Fi typically take another ten to thirty percent.
Related calculators
Data Transfer Time Calculator
Calculate how long a file transfer will take at a given throughput, and the effective speed you actually achieve.
Tech & ITDisk & Storage Calculator
Calculate usable capacity after RAID, formatting overhead, and growth — plus cloud storage cost.
Tech & ITMTU & MSS Calculator
Calculate the correct MTU and TCP MSS for tunnels, VPNs, and overlay networks with encapsulation overhead.
Tech & ITCIDR Calculator
Convert between CIDR notation and subnet masks, and see how many addresses each prefix length provides.
Tech & ITSpotted a problem, or want this calculator to do more?Corrections are fixed first, and the most-requested features get built next.Tell us →
Disclaimer. This calculator is provided for general information and educational purposes only and does not constitute financial, tax, legal, medical, or engineering advice. Results are estimates based on the inputs you provide and the assumptions described above. Confirm any figure with a qualified professional before acting on it.