Gigabyte to Exbibyte

Hard drive manufacturers measure 1 TB as 1,000,000,000,000 bytes (decimal). Windows displays storage in gibibytes (binary) but historically labelled them as "GB" — so 1,000,000,000,000 bytes ÷ 1,073,741,824 ≈ 931 GiB, which Windows displayed as "931 GB". macOS (since 10.6) correctly reports the same drive as "1 TB" using decimal GB. The drive is not lying; the OS was using a binary unit with a decimal label.

8 GB RAM is the current minimum for gaming; 16 GB is the recommended standard for most modern games at 1080p and 1440p; 32 GB benefits heavily multitasking systems or games with large open worlds. Memory-intensive tasks like video editing, 3D rendering, and running large language models locally typically require 32–64 GB or more.

A 4K movie in H.264 or H.265 encoding is typically 50–100 GB on Blu-ray; streaming services compress aggressively to 15–25 GB for 4K HDR content. Netflix's 4K streams average about 7 GB per hour; the downloaded version via the Netflix app for offline viewing is roughly 3–6 GB per hour at high quality settings.

1 GB of mobile data supports roughly: 2–3 hours of music streaming, 1 hour of HD video streaming, 2–3 hours of web browsing, or 30–60 minutes of video calling. Social media apps with autoplay video are heavy consumers — TikTok and Instagram Reels can use 300–600 MB per hour of active use.

AI model sizes vary enormously. GPT-2 (2019) is about 1.5 GB; Llama 2 7B is roughly 13 GB in float16 precision; Llama 2 70B is about 130 GB. GPT-4-class models are estimated at 500+ GB. Quantised (compressed) versions are smaller: a 4-bit quantised 7B model fits in about 4 GB, runnable on a modern laptop. Training requires far more — the training dataset, gradients, and optimizer states for a 70B model can occupy 1–2 TB of GPU memory across a cluster. The trend toward larger models is driving consumer GPU memory from 8 GB to 16–24 GB as a baseline for local AI inference.

EB (exabyte) = 10¹⁸ bytes (SI decimal). EiB (exbibyte) = 2⁶⁰ bytes = 1,152,921,504,606,846,976 bytes (IEC binary). EiB is 15.29% larger. This is the largest practically significant SI vs IEC discrepancy: per exbibyte, the binary value exceeds the decimal value by approximately 152,921,504,606,846,976 bytes — about 152.9 petabytes.

One exbibyte (EiB) ≈ 1.153 × 10¹⁸ bytes = 1,073,741,824 GiB = 1,048,576 TiB. In practical terms: enough to store approximately 230 billion JPEG photos at 5 MB each, or 288,230,376 copies of a 4 GB HD movie, or the entire text content of the English internet many thousands of times over.

In theory, yes — and with astonishing density. DNA can encode about 215 PiB per gram of material, meaning a single EiB could fit in roughly 4.7 grams of synthetic DNA. Researchers at Microsoft and the University of Washington have demonstrated writing and reading megabytes of data in DNA strands. The challenges are speed and cost: current DNA synthesis writes about 400 bytes per second and costs around $3,500 per megabyte. At that rate, writing 1 EiB would take billions of years and cost more than global GDP. However, enzymatic synthesis breakthroughs could reduce costs by 6–8 orders of magnitude within decades.

Storing 1 EiB on modern HDDs would require roughly 57,000 drives of 20 TB each, consuming about 400–500 kW of power just for the drives — plus 200–300 kW for cooling, networking, and overhead. That totals roughly 6 GWh per year, equivalent to powering about 550 US homes. At typical US grid carbon intensity, this produces around 2,500 tonnes of CO₂ annually. Hyperscale operators reduce this via renewable energy and immersion cooling, but the fundamental physics of spinning magnetic platters or maintaining NAND charge states sets a floor on energy consumption that no software optimisation can eliminate.

After exbibyte (EiB, 2⁶⁰ bytes) come: zebibyte (ZiB, 2⁷⁰ bytes) and yobibyte (YiB, 2⁸⁰ bytes), as defined in IEC 80000-13. These are recognized standard units but have no current practical applications. The entire global internet's estimated stored data (hundreds of EB) is still in the low hundreds of EiB range — well short of one ZiB.