Terabyte to Exabyte

1 terabyte (TB) = 1,000 gigabytes (GB) in the SI decimal system. In the binary IEC system, 1 tebibyte (TiB) = 1,024 gibibytes (GiB). Consumer hard drives and SSDs are labelled in decimal TB; operating systems may display available space in either GB or GiB depending on the OS and version, leading to a discrepancy of up to ~7% between the label and the OS display.

A 1 TB SSD holds approximately: 200,000 JPEG photos (at 5 MB each), 250 HD movies (at 4 GB each), 200+ modern AAA games (at 50 GB average), or enough for about 100 hours of 4K video footage from a modern camera. In practice, the OS and drive firmware overhead reduce usable capacity to roughly 900–930 GB as reported by the operating system.

A terabyte (TB) = 10¹² bytes = 1,000,000,000,000 bytes. A tebibyte (TiB) = 2⁴⁰ bytes = 1,099,511,627,776 bytes. The TiB is about 9.95% larger. This gap is why a 1 TB hard drive appears as 931 GiB (≈ 0.909 TiB) in Windows. The IEC formally defined TiB in 1998 to eliminate this naming ambiguity.

Timeline depends heavily on use case: continuous 4K video recording fills 1 TB in about 2–3 hours (at 1 GB/min). Typical laptop use (documents, photos, apps) might take 3–5 years to fill 1 TB. A game library of 20 modern AAA titles uses 500 GB–1 TB. Home security camera systems recording 24/7 at 1080p use about 1 TB every 10–15 days per camera.

For most individuals, 1 TB of cloud storage is generous: it holds 200,000+ photos, years of documents, and even video libraries. Google One offers 2 TB for €9.99/month; iCloud offers 2 TB for £6.99/month. Power users — especially photographers and videographers — may need 2–5 TB. Family sharing plans can make 2 TB cost-effective across multiple users.

One exabyte = 1,000,000 terabytes = 1,000 petabytes. If you filled 1 TB external hard drives and stacked them end to end, 1 EB worth would stretch roughly 200 km. In content terms: 1 EB can store about 250,000 years of HD video, or about 100 billion hours of music at 128 kbps. All the data produced by the Large Hadron Collider per year is about 15 petabytes — still 67× less than one exabyte.

Global data creation, capture, copy, and consumption is estimated at roughly 2.5 exabytes per day (IDC 2023 estimate), growing roughly 23% annually. This includes IoT sensor readings, financial transactions, social media posts, surveillance camera footage, scientific instrument output, and all other digital activity. Most of this data is transient and never stored long-term.

Amazon Web Services, Microsoft Azure, and Google Cloud each store estimated tens to hundreds of exabytes of customer data in their cloud platforms. Meta (Facebook/Instagram) stores an estimated 100+ exabytes across all data types. The NSA's Utah Data Center is estimated to hold yottabytes in capability, though actual stored volumes are classified. Collectively, global cloud storage is in the hundreds-of-exabytes range.

An exabyte (EB) = 10¹⁸ bytes (SI decimal). An exbibyte (EiB) = 2⁶⁰ bytes = 1,152,921,504,606,846,976 bytes — about 15.3% larger. This is the largest practically relevant gap between SI and IEC units in storage contexts. For a data center procuring 10 EB of storage, the SI vs IEC difference represents about 1.5 EB of capacity discrepancy in the contract.

Data archaeology is the practice of recovering information from obsolete storage media and formats — 9-track magnetic tapes, 8-inch floppy disks, MiniDiscs, Zip drives, and early optical formats. The challenge is threefold: hardware to read the media no longer exists or is failing, file formats and encoding schemes are undocumented, and magnetic media degrade over time (tape has a 10–30 year shelf life). At exabyte scale, organisations like national archives face the prospect of vast digital collections becoming unreadable within decades. Active migration strategies — periodically copying data to current formats and media — are the only reliable defense, but the cost scales linearly with data volume.