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Bandwidth Calculator

Estimate how long a file transfer or download will take, based on file size and connection speed.

About the Bandwidth Calculator

Estimate how long a file transfer or download will take, given the file size and your connection speed.

How the Bandwidth Calculator works

Internet speeds are usually advertised in megabits per second (Mbps), but file sizes are measured in megabytes (MB) — and there are 8 bits in a byte, so a "100 Mbps" connection tops out around 12.5 MB/s in practice, before accounting for overhead. This calculator converts both inputs to a common unit before dividing, so you don't have to do the bits-to-bytes conversion yourself.

How to use the Bandwidth Calculator

  1. Enter the file or data size and select its unit (KB, MB, GB, or TB).
  2. Enter your connection speed and select its unit (Kbps, Mbps, or Gbps).
  3. Press Calculate to see the estimated transfer time.

Tips for the Bandwidth Calculator

  • Real-world transfer speeds are usually somewhat lower than the advertised connection speed due to network overhead — treat this as a best-case estimate.

Formula used by the Bandwidth Calculator

Time = File Size (bits) ÷ Connection Speed (bits per second)

Example: Bandwidth Calculator

Downloading a 500 MB file on a 50 Mbps connection

  • File size: 500 MB
  • Connection speed: 50 Mbps

Result: ≈ 83.89 seconds

File size is measured in binary megabytes (1 MB = 1,048,576 bytes = 8,388,608 bits), while connection speed is measured in decimal megabits (1 Mbps = 1,000,000 bits/sec): 500 × 8,388,608 ÷ 50,000,000 ≈ 83.89 seconds, before any real-world overhead.

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