Download Speed Calculator
Estimate your real-world file download speeds and durations across fiber, cable, 5G, and satellite broadband connections.
Overview: Estimate your real-world file download speeds and durations across fiber, cable, 5G, and satellite broadband connections.
How the Download Speed Calculator Works Out Download Time
Duration = File Size in bits / (Speed in bps × Real-World Efficiency)Files are structured in 8-bit bytes. Network links transfer data in single-bit streams with packet headers and checksums.
Convert 25 GB to bits
25 GB × 8 = 200,000,000,000 bits
Apply 90% efficiency
200 Mbps × 0.90 ≈ 180 Mbps of usable download throughput after TCP/IP overhead.
Divide bits by throughput
25 GB at 200 Mbps takes 18 min 31 sec (theoretical minimum 16 min 40 sec).
Download Speed Calculator — Reference Table
Typical download durations for common file sizes, to sanity-check the result from the Download Speed Calculator.
| File Size | 10 Mbps | 25 Mbps | 50 Mbps | 100 Mbps | 200 Mbps | 500 Mbps | 1 Gbps |
|---|---|---|---|---|---|---|---|
| 100 MB | 1 min 29 sec | 36 seconds | 18 seconds | 8.9 seconds | 4.4 seconds | 1.8 seconds | 889 ms |
| 500 MB | 7 min 24 sec | 2 min 58 sec | 1 min 29 sec | 44 seconds | 22 seconds | 8.9 seconds | 4.4 seconds |
| 1 GB | 14 min 49 sec | 5 min 56 sec | 2 min 58 sec | 1 min 29 sec | 44 seconds | 18 seconds | 8.9 seconds |
| 5 GB | 1 hr 14 min 4 sec | 29 min 38 sec | 14 min 49 sec | 7 min 24 sec | 3 min 42 sec | 1 min 29 sec | 44 seconds |
| 10 GB | 2 hrs 28 min 9 sec | 59 min 16 sec | 29 min 38 sec | 14 min 49 sec | 7 min 24 sec | 2 min 58 sec | 1 min 29 sec |
| 25 GB | 6 hrs 10 min 22 sec | 2 hrs 28 min 9 sec | 1 hr 14 min 4 sec | 37 min 2 sec | 18 min 31 sec | 7 min 24 sec | 3 min 42 sec |
| 50 GB | 12 hrs 20 min 44 sec | 4 hrs 56 min 18 sec | 2 hrs 28 min 9 sec | 1 hr 14 min 4 sec | 37 min 2 sec | 14 min 49 sec | 7 min 24 sec |
| 100 GB | 1 day 41 min | 9 hrs 52 min 36 sec | 4 hrs 56 min 18 sec | 2 hrs 28 min 9 sec | 1 hr 14 min 4 sec | 29 min 38 sec | 14 min 49 sec |
Frequently Asked Questions About Download Speed Calculator
What is a good download speed for gaming and 4K streaming?
For 4K UHD video streaming, a minimum speed of 25 Mbps per stream is recommended. For online gaming, 50 to 100 Mbps provides ample headroom for low-latency gameplay and swift game updates.
How long does 100GB take to download at 500 Mbps?
At 500 Mbps with 90% efficiency, a 100GB file downloads in approximately 29 minutes and 38 seconds.