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Convert Gigabytes to Terabytes – Data Converter

This converter converts values between gigabytes (GB) and terabytes (TB) using standard unit definitions. By default, the conversion follows the SI (decimal) interpretation where 1 TB = 1,000 GB — the convention most storage manufacturers and data-traffic measurements use.

Storage and operating-system displays sometimes use binary prefixes (gibibyte, tebibyte) where 1 TiB = 1,024 GiB. This tool makes the decimal conversion explicit and includes guidance so you can choose the correct convention for your use case.

Updated Nov 25, 2025

Interactive Converter

Convert between gigabyte and terabyte with precision rounding.

Quick reference table

GigabyteTerabyte
1 GB0.13 TB
5 GB0.63 TB
10 GB1.25 TB
25 GB3.13 TB
50 GB6.25 TB
100 GB12.5 TB

Methodology

Decimal (SI) conversion: The International System of Units (SI) defines kilo-, mega-, giga-, tera- as powers of 10. Under this system 1 TB = 10^3 GB = 1,000 GB. This is the conversion applied by this GB → TB converter.

Binary (IEC) context: The International Electrotechnical Commission (IEC) introduced distinct binary prefixes (kibi-, mebi-, gibi-, tebi-) to denote powers of two. When working with binary-anchored systems (file systems, some OS reports, memory sizes), convert GiB ↔ TiB using factor 1,024. Consult the IEC/ISO and NIST references in the citations for authoritative details.

Worked examples

Example (decimal): 500 GB → 500 ÷ 1,000 = 0.5 TB.

Example (decimal): 1,000 GB → 1,000 ÷ 1,000 = 1 TB.

Binary comparison (for clarity): 1,024 GiB → 1,024 ÷ 1,024 = 1 TiB (binary).

Key takeaways

This converter returns decimal TB values from GB input using the SI factor (1 TB = 1,000 GB).

If you need binary-accurate conversions (GiB ↔ TiB), convert using powers of 2 (1,024) or use a dedicated GiB↔TiB converter and check byte-level counts for filesystem or device reporting.

Further resources

Expert Q&A

What exact conversion does this tool perform?

This converter uses the decimal (SI) relationship: 1 terabyte (TB) = 1,000 gigabytes (GB). The calculation is TB = GB ÷ 1000.

Why do my computer and my drive show different sizes?

Drive vendors report capacity in decimal (GB = 10^9 bytes). Operating systems sometimes report in binary (GiB = 2^30 bytes) but label as GB. The difference arises because 1,000^3 bytes (decimal) is smaller than 1,024^3 bytes (binary), producing different numeric labels for the same byte count.

What are GiB and TiB and when should I use them?

GiB (gibibyte) and TiB (tebibyte) are IEC binary prefixes that unambiguously mean powers of two: 1 GiB = 2^30 bytes, 1 TiB = 2^40 bytes. Use them when working with memory sizes, low-level filesystem metrics, or any context that requires exact binary multiples.

How should I round results for reporting or provisioning?

Round according to the audience and SLA. For consumer-facing summaries, two decimal places (e.g., 0.47 TB) is common. For capacity planning or billing, preserve at least three significant digits or display both GB and TB with exact byte counts to avoid ambiguity.

Does this converter account for filesystem overhead or formatting?

No. This converter maps unit quantities only. Filesystem metadata, reserved space, compression, thin provisioning, and block-alignment reduce usable capacity; measure usable bytes on the target system to account for those effects.

How can I convert between GB and GiB (decimal vs binary)?

To approximate GiB from GB, divide by 1,000 then multiply by 1,024 where appropriate; more precisely, convert bytes first (bytes = GB × 10^9), then divide by 2^30 to get GiB. For accuracy, convert via bytes: GiB = (GB × 10^9) ÷ 2^30.

Sources & citations