Your hosting plan says 5 GB. Your file manager says the folder is 4.66 GiB. Both numbers are right, and this file size converter shows why. It takes one value and prints it in nine units at once: B, KB, MB, GB, TB, PB, KiB, MiB and GiB. A second panel on the page turns CSS pixels into rem and pt.
Why one file has two sizes
KB, MB and GB count in steps of 1000. KiB, MiB and GiB count in steps of 1024. The gap grows with each level: about 2.4% at kilo, 4.9% at mega and 7.4% at giga. Three places where it bites:
- A video export of 24.1 MiB is 25.2707 MB. A mail limit of 25 MB rejects it, although 24.1 looks safe.
- A phone sold as 128 GB: about 119.2 GiB in the settings.
- Disk with 1 TB on the box. The system shows 931.3226 GiB, because the maker counts in thousands and the system in 1024s. Nothing is missing.
Four steps through the file size converter
- Type a number into the field under Enter value. It starts at 1024.
- Pick the unit of that number in the select box next to it. The default is Megabytes (MB).
- Read the list Results in all units. It changes on every keystroke, so there is no convert button.
- For CSS, set the Base font size (16 by default), type a value into Pixels (px) and read the rem and pt fields.
Pixels, rem and points
Say a designer hands over 14 px body text. With the default base of 16 that is 0.875 rem and 10.5 pt. If your project sets the root to 10 px, change the base size to 10 and the same text is 1.4 rem. Points use the CSS ratio of 0.75 pt per px, which means 96 pixels per inch. A base size of 0 falls back to 16. There is no em output, because em depends on the parent element and the tool cannot know it.
Where the numbers stop being plain
The storage list ends at PB. There are no TiB or PiB rows. All math uses JavaScript floating-point numbers, which stay exact for whole byte counts up to 2^53, roughly 9 PB.
Results from 0.0001 up to just under one trillion appear as normal numbers with at most four decimals. Anything outside that range switches to exponent form, for example 1.0000e-5. A zero, an empty field or a negative value is shown in that form too. In the typography panel, rem is rounded to four decimals and points to two.
No network traffic while you type
Every conversion is plain arithmetic in your browser. Nothing is sent, and the page has no upload step. Open the network panel in your developer tools, type a few numbers and watch the request list stay empty. The tool does not use the clipboard, does not create a download and does not store your values.