Bandwidth Calculator
Calculate bandwidth needs for video streaming, downloads, or office connectivity. Convert between Mbps, MB/s, and GB per hour.
What is Bandwidth Calculator?
The bandwidth calculator converts between Mbps (the marketing unit) and MB/s (the actual data rate), then estimates download time for any file size.
Formula
1 byte = 8 bits. So 100 Mbps = 100/8 = 12.5 MB/s. Download time = file size in MB ÷ MB/s.
Worked example
Downloading a 5 GB game on a 100 Mbps connection: 5,120 MB ÷ 12.5 MB/s = 410 s ≈ 6m 50s.
How to use this calculator
- Enter your internet speed in Mbps.
- Enter file size and pick its unit (KB/MB/GB/TB).
- The download time, MB/s rate, and hourly/daily throughput appear.
Frequently asked questions
Why is my actual speed slower than my plan?
Many ISPs advertise the maximum speed. Real speeds vary with router, distance to server, peak hours, and overhead (TCP, encryption). 70–80% of plan speed is normal in real-world conditions.
What is the difference between Mbps and MBps?
Mbps is megabits per second — a transfer rate. MBps is megabytes per second — a data rate. 1 byte = 8 bits. ISPs use Mbps because it sounds bigger; you actually receive 1/8 that in megabytes.
What bandwidth do I need for streaming?
SD video: 3 Mbps. HD: 5 Mbps. 4K: 25 Mbps. Multiple devices share a connection, so for a 4-person household streaming 4K simultaneously: 4 × 25 = 100 Mbps minimum.
Are there speed bottlenecks beyond the ISP?
Yes. Older routers cap at 100 Mbps. Older Wi-Fi (b/g) maxes around 54 Mbps. Ethernet over Cat 5e supports up to 1 Gbps; Cat 6 up to 10 Gbps. Phone or laptop chips also limit speeds.