Web Page Resource Analyzer - Online List Assets & Size
Fetch a page and list all loaded assets (CSS, JS, images) with their sizes. See total page weight. Quick performance check.
UD5 Toolkit
Mbps ≠ MB/s! Internet speeds are advertised in Megabits per second (Mbps), while browsers show downloads in Megabytes per second (MB/s).
1 MB/s = 8 Mbps
A 100 Mbps connection gives you ~12.5 MB/s maximum download speed (before overhead).
To calculate download time, use this formula:
Download Time (seconds) = File Size (bits) ÷ Bandwidth (bits per second)
Step-by-step:
For example, a 1 GB file (8,589,934,592 bits) on a 100 Mbps connection (100,000,000 bps) takes approximately 85.9 seconds theoretically, or about 95 seconds with 10% overhead.
Several factors cause real-world speeds to be lower than advertised:
Use our overhead slider to estimate real-world download times more accurately.
Mbps (Megabits per second) and MB/s (Megabytes per second) measure different things:
Quick conversion:
Speed in MB/s = Speed in Mbps ÷ 8
So a 100 Mbps connection = ~12.5 MB/s theoretical maximum download speed. With 10% overhead, expect around 11.25 MB/s in practice.
Here are typical download times on a 100 Mbps connection (with 10% overhead):
| File | Size | Download Time |
|---|---|---|
| Music Album (MP3) | 100 MB | ~9 seconds |
| YouTube 1080p (10 min) | 500 MB | ~44 seconds |
| Windows 11 ISO | 6 GB | ~9 minutes |
| Netflix 4K Movie | 14 GB | ~21 minutes |
| PS5 Game | 80 GB | ~2 hours |
| 1 TB Backup | 1 TB | ~25 hours |
Times are approximate and account for 10% protocol overhead.
Protocol overhead refers to the extra data transmitted alongside your actual file content. This includes:
In practice, overhead typically consumes 5-15% of your total bandwidth. Our calculator's overhead slider lets you model this for more realistic estimates.
To maximize download speeds:
Yes! Many servers compress files before transfer. This means:
For estimating downloads from web servers, the actual transferred size may be smaller than what you see saved on disk. Our calculator uses the uncompressed file size for conservative estimates.
For smooth 4K streaming, recommended minimum speeds are:
For a household with multiple 4K streams plus other usage, 100-300 Mbps is recommended. Use our Bandwidth Calculator tab to determine exactly what you need based on your file sizes and desired download times.
Fetch a page and list all loaded assets (CSS, JS, images) with their sizes. See total page weight. Quick performance check.
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