Why is my actual download speed slower than advertised?

ISPs advertise maximum speeds under ideal conditions. Real-world speeds are reduced by network congestion, distance from exchange, router quality, Wi-Fi interference, and server-side limits. Typically you get 60-80% of the advertised rate.

What is the difference between Mbps and MB/s?

Mbps (megabits per second) is the unit ISPs use for marketing. MB/s (megabytes per second) is used for file sizes. 1 byte = 8 bits, so 100 Mbps ÷ 8 = 12.5 MB/s actual file transfer speed.

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Download Time Calculator

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Download Time Calculator

Common File Sizes

File Size

Download Speed

Upload Speed (same unit)

Privacy First: Your files are processed securely. Whenever possible, processing happens in your browser and files are never stored on our servers.

Calculate download/upload time from file size and connection speed. File presets: MP3, movie, game. Speed presets: dial-up to fiber 5G. Speed comparison table. Upload time separate.

How to Use

1Click a file size preset (MP3, movie, game) or enter a custom size and unit
2Click a speed preset (Dial-up, DSL, Cable, Fiber, 4G, 5G) or enter your connection speed
3Click Calculate to see download time and upload time
4The comparison table shows time at all 6 preset speeds for the entered file size
5Note: actual download speed is typically 60-80% of advertised speed

Features

File size units: KB, MB, GB, TB
Speed units: bps, Kbps, Mbps, Gbps, KB/s, MB/s, GB/s
Upload time calculation with separate speed input
Speed comparison table at 6 presets (Dial-up to 5G)
File size presets (MP3, movie, game, ISO)
100% browser-based

Download Time Calculator

Download Time Calculator

How to Use

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Frequently Asked Questions

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