Megabit to Petabyte

Divide Mbps by 8 to get megabytes per second (MB/s). A 100 Mbps connection = 12.5 MB/s. A 1 Gbps connection = 125 MB/s. This conversion is essential when comparing advertised internet speeds (always in Mbps) to actual file download speeds (shown in MB/s by browsers and download managers).

Netflix recommends 25 Mbps for 4K Ultra HD. Disney+ and Apple TV+ recommend 25 Mbps; YouTube recommends 20 Mbps for 4K. These are per-stream figures — a household streaming two 4K sources simultaneously needs roughly 50 Mbps of reliable throughput, plus headroom for other devices.

ISP speed ratings are theoretical maximums under ideal conditions. Real-world factors include network congestion, router quality, Wi-Fi interference, the server's upload speed, and protocol overhead. Additionally, browsers and download managers report speeds in MB/s (bytes), which is 8× smaller than the Mbps figure — a 100 Mbps plan showing 11 MB/s in a browser is performing normally.

One gigabit equals 1,000 megabits (SI decimal system). Gigabit broadband (1 Gbps) = 1,000 Mbps = 125 MB/s theoretical download speed. In the binary IEC system, one gibibit = 1,024 mebibits — but for internet speeds the SI decimal values are always used.

Fiber-to-the-home (FTTH) delivers symmetric speeds of 100–10,000 Mbps with consistent performance regardless of distance from the exchange. Cable (DOCSIS 3.1) offers 100–1,200 Mbps download but typically 10–50 Mbps upload, and throughput degrades during neighborhood peak hours due to shared bandwidth. DSL (VDSL2) maxes out at 50–100 Mbps download and drops sharply beyond 500 meters from the DSLAM cabinet. In practice, most cable users see 60–80% of advertised speeds; DSL users at distance may see under 50%. Fiber is the only technology that reliably delivers its rated megabit throughput.

1 petabyte (PB) = 1,000 terabytes (TB) in the SI decimal system. In the binary IEC system, 1 pebibyte (PiB) = 1,024 tebibytes (TiB) = 1,125,899,906,842,624 bytes. The distinction matters for enterprise storage procurement: a petabyte of raw disk capacity appears as about 909 TiB in an OS reporting binary units.

Petabyte-scale storage is common at: social media platforms (Facebook/Meta stores over 100 PB of photos alone), streaming services (Netflix's content library is estimated at 100+ PB), government agencies (US NSA, CERN particle physics data), genomic research institutions, and large financial exchanges storing tick-level trading data. Major cloud providers (AWS, Azure, GCP) collectively store zettabytes.

In 2024, cloud storage costs roughly $20–25 per TB per month (S3 standard tier), making 1 PB approximately $20,000–$25,000/month. Raw enterprise disk hardware for 1 PB runs about $20,000–$50,000 upfront (at $20–50 per TB for high-density drives), plus ongoing power, cooling, and management overhead. Tape-based archival storage is considerably cheaper at $2–5 per TB.

YouTube users upload approximately 500 hours of video per minute, or 720,000 hours per day. At an average compressed size of 1–2 GB per hour of HD video, that equates to roughly 720–1,440 TB (0.7–1.4 PB) of new video data per day — before YouTube re-encodes into multiple formats and quality levels, which multiplies storage requirements several-fold.

The SI prefix hierarchy above petabyte: exabyte (EB, 10¹⁸ bytes), zettabyte (ZB, 10²¹ bytes), yottabyte (YB, 10²⁴ bytes), ronnabyte (RB, 10²⁷ bytes), and quettabyte (QB, 10³⁰ bytes) — the last two added by the BIPM in 2022. Current global data storage is estimated in the hundreds of exabytes; no single organisation approaches yottabyte scale.