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Key Features
Instant Calculation
Get accurate results in real time with our optimized algorithm.
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Connection speeds are advertised in megabits per second, but file sizes are measured in megabytes or gigabytes — an easy source of confusion when estimating download times.
This calculator converts between the two and estimates how long a file will take to download at a given connection speed.
How it works
Enter the file size (in MB, GB, or TB) and your connection speed in Mbps. The calculator converts the file size to megabits (multiplying bytes by 8, since connection speeds are measured in bits), then divides by your connection speed.
- Enter file size.
- Enter file size unit.
- Enter connection speed (Mbps).
- Click Calculate to see your results.
Examples
1.5 GB file at 100 Mbps
A 1.5 GB file downloading at a steady 100 Mbps takes about 122.88 seconds — roughly 2 minutes.
Who should use it
- Estimating how long a large file, game, or software update will take to download.
- Comparing expected download times across different internet plans.
Industry applications
- IT and network administration
- Consumer internet service comparisons
Advantages
- Handles the common bits-vs-bytes confusion automatically.
- Supports MB, GB, and TB file sizes in one calculator.
Limitations
- Assumes a constant, uninterrupted connection speed for the whole download — real-world speeds fluctuate.
Common mistakes to avoid
- Entering a MBps value (megabytes) where Mbps (megabits) is expected, which understates the download time by a factor of 8.
- Assuming real-world speeds always match the advertised maximum connection speed.
Best practices
- Run a speed test to check your actual current connection speed rather than relying solely on your plan's advertised maximum.
Tips
- Actual throughput is often 80-90% of the advertised maximum speed in practice — for a more conservative estimate, try entering roughly 85% of your plan's advertised speed.