Advertised speed is not download speed
ISPs advertise megabits per second (Mbps). Downloaders measure megabytes per second (MB/s). Because there are 8 bits in a byte, a “100 Mbps” plan tops out near 12.5 MB/s in perfect conditions — and Steam, Epic or Battle.net rarely sustain that on Wi‑Fi.
This calculator lets you enter either Mbps or MB/s and optionally add overhead so the ETA matches what you actually see in a launcher.
How to measure a realistic speed for the estimate
Start a download in your game launcher, note the stable MB/s after the first minute, and enter that as MB/s with low overhead. Or run a wired speed test, enter the Mbps result, and keep 10% overhead as a default for Wi‑Fi congestion and TCP overhead.
CDN routing, peak-hour congestion and disk write speed can all stretch the final install time beyond the pure network estimate — especially on HDDs while a large game decompresses.
Using ETAs for updates vs full installs
Patch sizes are often smaller than the full game but can still take longer than expected if the launcher re-verifies or re-downloads compressed chunks. Use the patch size from the launcher’s download details when available, not the storefront “install size,” which usually includes already-owned content.
Privacy
Size and speed inputs never leave your browser. GameFixZone does not monitor your network.
Frequently Asked Questions
Why is my Steam download slower than a speed test?
Speed tests hit nearby servers under ideal conditions. Game CDNs may be farther away, shared with other users, or limited by disk writes and launcher settings such as bandwidth caps or too many/too few download threads.
Should I use Mbps or MB/s?
Use Mbps for plan or speed-test numbers. Use MB/s when reading the live rate inside Steam, Epic, Battle.net or Xbox apps.
What overhead percentage should I pick?
0–5% on a quiet wired connection, around 10% for typical Wi‑Fi, and 15%+ if the network is busy or the launcher frequently stalls.
Is anything uploaded?
No. The estimate is calculated entirely on your device.
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