Download Time Calculator
Calculate how long a file download will take based on file size and connection speed. Includes presets for 3G, 4G, 5G, DSL, fiber, and gigabit. Free, 100% in your browser.
Reference
How is download time calculated?
Download time = (file size in bits) ÷ (speed in bits per second). A byte = 8 bits, so a 1 MB file = 8 megabits. Network speeds are typically advertised in megabits per second (Mbps), while file sizes use megabytes (MB). This is why a "100 Mbps" connection downloads a 100 MB file in about 8 seconds, not 1 second. Real-world speeds are usually 60-80% of advertised speeds due to overhead, latency, and congestion.
Connection speed reference
3G mobile: 1-10 Mbps. 4G LTE: 10-50 Mbps. 5G: 100-1000 Mbps. DSL: 5-35 Mbps. Cable: 25-300 Mbps. Fiber: 100-1000 Mbps. Gigabit: 1000 Mbps. WiFi 6: up to 1200 Mbps (theoretical). Actual speeds vary by location, provider, time of day, and network congestion.
Common use cases
Large downloads — estimate time for game downloads, OS updates, or video files. Cloud uploads — plan backup schedules for large datasets. Video streaming — check if your connection can handle 4K streaming (requires ~25 Mbps). Remote work — estimate file transfer times for sending large assets. Travel — plan downloads before switching to slower mobile connections.
Privacy
All calculations run 100% in your browser. No data is sent to any server.