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TechYour ISP promises 200 Mbps. Your download crawls at 25 MB/s. Did you get scammed? No — you just met the most confusing capitalization in technology: lowercase b means bits, uppercase B means bytes, and one byte is eight bits.
This guide untangles bits vs. bytes, explains why a "1 TB" drive shows less, and translates advertised speeds into the download rates you'll actually see.
Try it yourself: Convert between bits, bytes, KB, MB, GB, and TB. Data Storage Converter →
Bits vs. bytes: the 8x rule
A bit is a single 1 or 0. A byte is 8 bits — historically the amount needed to store one text character. The convention:
- Network speeds use bits: Mbps, Gbps (your ISP, speed tests).
- File sizes and storage use bytes: MB, GB, TB (your downloads, hard drive).
MB/s = Mbps ÷ 8
So 200 Mbps ÷ 8 = 25 MB/s maximum — your "slow" download was actually running at full speed.
What common speeds really mean
| Advertised | Max download rate | A 5 GB file takes |
|---|---|---|
| 25 Mbps | 3.1 MB/s | ~27 min |
| 100 Mbps | 12.5 MB/s | ~7 min |
| 500 Mbps | 62.5 MB/s | ~80 sec |
| 1 Gbps | 125 MB/s | ~40 sec |
These are theoretical maximums — real speeds run 10–30% lower (see our download-time guide).
Why your 1 TB drive shows 931 GB
Storage makers define 1 GB as 1,000 MB (decimal). Operating systems traditionally divide by 1,024 (binary) and — confusingly — still label the result "GB" instead of "GiB". So 1,000,000,000,000 bytes ÷ 1,024³ = ~931 "GB". Nothing is missing; the ruler changed. The binary units (KiB, MiB, GiB, TiB) exist precisely to end this confusion, but adoption is slow.
How much speed do you actually need?
- 25 Mbps — fine for a person or two: HD streaming (~5 Mbps), video calls (~2–5 Mbps), browsing.
- 100 Mbps — comfortable for a family: multiple 4K streams (~25 Mbps each) plus gaming.
- 500+ Mbps — only matters for huge downloads, creators uploading video, or many simultaneous heavy users.
Latency (ping) matters more than raw speed for gaming and video calls — 25 Mbps with low ping beats 500 Mbps with high ping for real-time use.
Upload speeds: the forgotten half
Most home plans are asymmetric: 100 Mbps down might mean 10 Mbps up. That's fine for streaming but painful for creators — uploading a 2 GB video file at 10 Mbps takes (2,000 × 8) ÷ 10 = 1,600 seconds, about 27 minutes. Video calls need only 2–5 Mbps up, but cloud backups, YouTube uploads, and large email attachments live and die by upload speed. If you create content, shop plans by the upload number, not the download headline.
Data caps in perspective
Many plans cap monthly data (often 1 TB). What does 1 TB actually buy? Roughly 140 hours of 4K streaming (~7 GB/hr), 500 hours of HD (~2 GB/hr), or about 200 AAA game downloads. For typical households it's plenty; for a house full of 4K streamers and game downloads, it's worth monitoring. Your ISP's usage meter — not your gut — is the source of truth.
5G vs. home broadband
5G routinely delivers 100–500 Mbps — competitive with cable on raw speed — but with higher latency variation and data caps that make it expensive as a full home replacement for heavy users. As a backup connection or for light households, it's genuinely viable; for 4K-everything families, wired broadband still wins on consistency and cost per gigabyte.
Know your actual usage before upgrading
Before paying for a faster tier, check what you use: most routers and ISP apps show per-device consumption. A household streaming 4K a few hours daily plus normal browsing rarely sustains over 50 Mbps — if your 100 Mbps plan feels slow, the culprit is almost always Wi-Fi coverage or latency, not bandwidth. A $30 access point often fixes what a $30/month upgrade won't.
Frequently asked questions
For most households, yes. It supports several simultaneous 4K streams (~25 Mbps each), video calls, and gaming with headroom. Only large-file downloaders and video creators benefit much from going faster.
Manufacturers count 1 GB as 1,000 MB while your OS divides by 1,024 and still calls it GB. 1 trillion bytes ÷ 1,024³ ≈ 931 GB — the space is all there, measured with a different ruler.
GB is decimal (1,000 MB, used by storage makers); GiB is binary (1,024 MiB, used by operating systems). The 'iB' units were created to end exactly this confusion.
Neither matters much — gaming needs under 5 Mbps. Latency (ping) is what affects gaming and video calls, not raw download speed.
Disclaimer: Speeds shown are theoretical maximums. Actual throughput depends on network conditions, Wi-Fi quality, and server capacity.