File Size Converter
Convert bytes, KB, MB, GB and TB, compare 1000-based and 1024-based results, and understand what your file size or storage capacity really means.
This is a file size and data storage unit converter, not a file compressor.Convert file size and data storage units
Choose decimal for storage devices, internet data, phone plans and marketing-style capacity. Choose binary when you want 1024-based computer-style calculations.
Check a local file size without uploading it
Select a file to read its size in your browser. The file stays on your device; this page only reads the file size value.
Common file size conversions
People usually search for very specific conversions such as GB to MB, MB to GB, KB to MB, MB to KB, TB to GB, or bytes to GB. The table below shows both decimal and binary-style answers where the difference matters.
| Conversion | Decimal result | Binary-style result | When it is commonly used |
|---|---|---|---|
| 1 GB to MB | 1000 MB | 1024 MiB | Phones, data plans, drives vs operating systems |
| 5 GB to MB | 5000 MB | 5120 MiB | Mobile data, video files, cloud transfer limits |
| 10 GB to MB | 10000 MB | 10240 MiB | Downloads, game patches, backup estimates |
| 500 MB to GB | 0.5 GB | 0.488 GiB | Email attachments, PDF limits, app downloads |
| 1024 MB to GB | 1.024 GB | 1 GiB | Binary-style memory and operating system examples |
| 1 TB to GB | 1000 GB | 1024 GiB | Storage drives, external disks, backup drives |
| 1 MB to KB | 1000 KB | 1024 KiB | Documents, images, upload size limits |
| 1 GB to bytes | 1,000,000,000 bytes | 1,073,741,824 bytes | Technical checks, storage math, scripts |
Is 1 GB 1000 MB or 1024 MB?
Both answers can be correct, but they describe different systems. The confusion comes from the way everyday storage products, internet plans, operating systems, and older computer terminology use similar-looking labels.
Decimal storage: 1000-based
In the decimal system, each larger unit is 1000 of the previous unit. This is common for hard drives, SSDs, phone storage, cloud storage, internet data plans, and marketing-style capacity.
- 1 KB = 1000 bytes
- 1 MB = 1000 KB = 1,000,000 bytes
- 1 GB = 1000 MB = 1,000,000,000 bytes
- 1 TB = 1000 GB = 1,000,000,000,000 bytes
Binary storage: 1024-based
In the binary system, each larger unit is 1024 of the previous unit. The clearer labels are KiB, MiB, GiB and TiB, although many users still say KB, MB, GB and TB casually.
- 1 KiB = 1024 bytes
- 1 MiB = 1024 KiB = 1,048,576 bytes
- 1 GiB = 1024 MiB = 1,073,741,824 bytes
- 1 TiB = 1024 GiB = 1,099,511,627,776 bytes
If you are comparing a storage product, phone plan, cloud plan, file transfer limit, or internet data allowance, decimal is often the practical choice. If you are checking how an operating system or technical tool displays capacity, binary-style values may explain the difference you see.
MB vs MiB and GB vs GiB
MB and MiB are not exactly the same. GB and GiB are not exactly the same either. The difference is small for tiny files, but it becomes noticeable for large videos, games, backups, and disk capacities.
| Label | Meaning | Bytes | Plain-English note |
|---|---|---|---|
| MB | Megabyte | 1,000,000 bytes | Decimal; common in storage products and file marketing |
| MiB | Mebibyte | 1,048,576 bytes | Binary; common in precise computer calculations |
| GB | Gigabyte | 1,000,000,000 bytes | Decimal; common for data plans, drives and cloud storage |
| GiB | Gibibyte | 1,073,741,824 bytes | Binary; often close to what an OS capacity display implies |
| TB | Terabyte | 1,000,000,000,000 bytes | Decimal; common on storage device packaging |
| TiB | Tebibyte | 1,099,511,627,776 bytes | Binary; useful when explaining apparent capacity loss |
Why does my 1 TB drive show less space?
A 1 TB drive often appears as roughly 931 GiB in a computer interface. That does not necessarily mean the drive is defective. It usually means the manufacturer advertised the drive using decimal terabytes while the operating system is displaying a binary-style number.
For example, 1 TB in decimal is 1,000,000,000,000 bytes. If you divide that by 1024 three times to express it in GiB, the result is about 931.32 GiB. Formatting, partitions, recovery files, system metadata, and preinstalled content can reduce the usable space further.
This is why a phone, SSD, USB drive, SD card, or external drive can appear smaller after you connect it to a computer. The advertised capacity and the displayed capacity may be using different unit systems.
File size examples for real-life decisions
Unit conversion is useful, but most users are really trying to answer practical questions: Can I upload this file? Will it fit on my drive? How much cloud storage do I need? How large is this download in GB?
- Photos: A compressed phone photo may be 2 MB to 8 MB, while a RAW photo can be much larger. Use MB to GB when estimating how many photos fit in cloud storage.
- PDFs: A small PDF may be under 1 MB, but scanned documents can be 25 MB or more. Upload limits are often shown in MB.
- Videos: Short videos can quickly reach hundreds of MB. Long HD or 4K videos often need GB-level storage.
- Games: Game downloads and updates are commonly shown in GB. Use GB to MB if a launcher, device, or limit uses MB.
- Backups: Phone, laptop, and photo-library backups often need GB or TB estimates. Decimal capacity is useful for product sizing; binary can help explain operating system displays.
- USB drives and SD cards: A 128 GB card is usually sold using decimal GB. Your device may show a slightly different binary-style capacity.
How to choose decimal or binary mode
When you are not sure which mode to use, show both. That is the safest option because it makes the difference visible instead of hiding it behind one answer.
| Your situation | Recommended mode | Reason |
|---|---|---|
| Hard drive, SSD, USB drive, SD card advertised capacity | Decimal | Storage products are usually marketed with 1000-based units. |
| Phone storage or cloud storage plan | Decimal | Consumer storage plans are usually listed in decimal GB or TB. |
| Operating system capacity display | Binary or show both | The display may effectively use binary-style values. |
| Memory-style or technical calculations | Binary | 1024-based units are common in technical contexts. |
| Explaining a file size to a non-technical user | Decimal or show both | Decimal is easier to understand, but both avoids confusion. |
How to use this data storage converter
- Enter the amount, such as 1, 500, 1024, 10000, or 1.5.
- Select the source unit, such as MB, GB, TB, bytes, MiB or GiB.
- Select the target unit, such as GB, MB, bytes or TB.
- Choose decimal, binary, or show both. If you are unsure, choose show both.
- Read the result and the explanation below it.
You can also choose a local file to see its size in bytes, KB, MB, GB, KiB, MiB and GiB. This is useful when you need to know whether a file fits under an upload limit or email attachment limit.
FAQ
How many MB are in a GB?
In decimal storage, 1 GB equals 1000 MB. In binary-style storage, 1 GiB equals 1024 MiB. If a tool or website does not explain which system it uses, that can cause confusion.
How many KB are in an MB?
In decimal storage, 1 MB equals 1000 KB. In binary-style storage, 1 MiB equals 1024 KiB.
Is this a file compressor?
No. This page converts and explains file size units. It does not reduce or compress files. If you need to shrink a PDF, image, video or ZIP file, you need a file compression tool.
Can I convert GB to bytes?
Yes. Select GB as the source unit and bytes as the target unit. In decimal mode, 1 GB equals 1,000,000,000 bytes. In binary mode, 1 GiB equals 1,073,741,824 bytes.
Why do Google answers sometimes say 1 GB = 1000 MB?
Many quick answers use decimal storage units because those are standard for many consumer storage and data-plan contexts. But binary-style answers still appear in computer memory and operating-system discussions.
Related calculators
Continue with other WideCalculator tools for practical planning and everyday estimates.
This calculator is for unit conversion and planning estimates. Always check the official limit, device specification, upload rule, or operating-system display when exact capacity matters.