Download Time Calculator
How long a file takes at your connection speed โ Mbps vs MB/s untangled.
Estimating a download
File size, connection speed, answer โ plus a comparison table across common connection types, and presets from a photo to an 80 GB game. Speeds can be entered in Mbps (how plans are sold) or MB/s (what download screens show), which is precisely the trap the tool exists to untangle.
Bits, bytes, and why your download 'runs at an eighth'
Internet plans are sold in megabits per second; files are measured in megabytes; a byte is eight bits. A 100 Mbps line therefore moves about 12.5 MB/s โ so a browser showing 12 MB/s is the plan working perfectly, not the provider cheating you by 8ร. This single confusion powers a remarkable share of ISP support calls.
Real downloads run 10โ20% below the calculator: protocol overhead, server limits, Wi-Fi interference and housemates all take a share. If wired downloads consistently sit far below the plan's figure, that is a conversation with the provider. The compression guide covers why the file might be smaller than feared in the first place, and the unit converter handles the general MB/GB arithmetic.
Frequently asked questions
How long does a 4 GB file take to download?
About 5ยฝ minutes at 100 Mbps, 11 at 50, an hour at 10. The table shows your file across all common speeds.
Why does my 100 Mbps connection download at 12 MB/s?
Because that is correct: 100 megabits รท 8 = 12.5 megabytes per second. Plans are sold in bits, download meters show bytes.
Why are my real downloads slower than the estimate?
Overhead, server throttling, Wi-Fi losses and shared usage typically cost 10-20%. The estimate is the physical ceiling of the connection.
Is upload speed the same as download?
Rarely โ most home connections are asymmetric, with upload a fraction of download. For sending large files, check the upload figure on your plan and enter that instead.