File Size ConverterConvert file sizes between bytes, kilobytes, megabytes, gigabytes and terabytes in both decimal (1000) and binary (1024) units — or drop a file to see its exact size.
Download Time Calculator
Internet speeds are sold in megabits per second, but file sizes are in megabytes — a factor of 8 apart. Enter both and this calculator converts them, adds a realistic overhead allowance and shows the expected time, plus a comparison table of common speeds.
Runs entirely in your browser. Your input and files are not uploaded to any server.
How to use
- Enter the file size and unit.
- Enter your connection speed and its unit.
- Adjust the overhead if you know your real-world efficiency.
Examples
Game download
80 GB at 100 Mbps with 10% overhead ≈ 1 h 58 min.
Video upload
2 GB at 20 Mbps upload ≈ 14 min 49 s.
Privacy
Runs entirely in your browser. Your input and files are not uploaded to any server. See the privacy policy for what is stored in your browser (favorites and history only). Privacy policy
Check it yourself: open your browser’s developer tools, select the Network tab and use the tool. Your file never appears in an upload request. Once this page is saved for offline use, you can also disconnect from the internet and keep working. Ads and anonymous visit statistics, when enabled, make their own requests, but they never receive your files or text.
Frequently asked questions
Why is my real download slower?
Server limits, Wi-Fi quality, other devices on the network and distance to the server all matter. The overhead setting covers protocol headers, not these factors.
Mbps or MB/s?
Mbps is megabits per second (what providers advertise). MB/s is megabytes per second (what download managers often show). 1 MB/s = 8 Mbps.
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