Why is transfer time different from what I experience?

Real-world transfers are affected by protocol overhead, latency, congestion, and server-side limits. This calculator gives the theoretical maximum speed.

What is the difference between Mbps and MB/s?

Mbps is megabits per second (used for network speeds). MB/s is megabytes per second (used for file sizes). 1 byte = 8 bits, so 100 Mbps ≈ 12.5 MB/s.

Does this support base-2 (MiB) calculations?

This calculator uses base-10 (SI) units: 1 KB = 1,000 bytes, 1 MB = 1,000,000 bytes. Most networking standards use base-10.

What is the reverse mode?

Reverse mode calculates the required bandwidth to transfer a file of a given size within a target time. Useful for provisioning network capacity.

Bandwidth Calculator

Calculate file transfer time from size and speed, or determine the required bandwidth for a target transfer time.

File Size

Size of the file or data to transfer.

Unit

Speed

Your network connection speed.

Unit

Transfer Time

1m 20s

to transfer 1 GB at 100 Mbps

Breakdown

Days

Hours

Minutes

Seconds

Total: 80 seconds

Documentation

How It Works

The calculator converts your file size to bits and your speed to bits per second, then divides to get the transfer time. In reverse mode, it divides the total bits by the target time to get the required speed.

Important: Network speeds are measured in bits (Mbps), while file sizes are measured in bytes (MB). 1 byte = 8 bits.

Formula

Time: (File Size × 8) ÷ Speed

Speed: (File Size × 8) ÷ Time

1 Byte: = 8 Bits

1 Mbps: = 1,000,000 bits/second

Last Updated: February 2026

Note: Actual transfer times may vary due to protocol overhead, latency, and congestion.

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Frequently Asked Questions

How to Use

About the Bandwidth Calculator

What it calculates

This bandwidth calculator helps with subnetting, bandwidth, DNS TTL, and other IT networking calculations. Estimate transfer time from file size and speed, or calculate required bandwidth.

When to use it

Use for network planning, certification prep, and sysadmin troubleshooting.

Example

Adjust the inputs above to model your specific scenario with the Bandwidth Calculator.

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Bandwidth Calculator

1m 20s

Breakdown

How It Works

Formula

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About the Bandwidth Calculator

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