PB to MB Converter

How many megabytes are in a petabyte?

1 MB = 1,000,000,000 PB in SI counting, the system that the International System of Units defines and storage vendors use. In binary counting 1 MiB = 1,073,741,824 PiB; the binary units carry the IEC names mebibytes and pebibytes.

MB = PB ÷ 1,000,000,000 (SI)

MiB = PiB ÷ 1,073,741,824 (binary)

The converter opens with Use SI standard ticked. Clear the box to count in powers of 1,024; the labels then change to PiB and MiB, so you can tell which system an answer belongs to.

Where PB to MB comes up

Megabytes are the size of a photo or a song, which makes the megabyte count of a petabyte a vivid way to describe scale: one petabyte is a billion megabytes in SI counting. Software that reports quotas or usage in MB may also need to be fed a petabyte figure converted down.

How to convert PB to MB

1. Type the number of petabytes in the first box.
2. Leave Use SI standard ticked for thousands, or clear it for 1,024s.
3. The MegaBytes box shows the answer as you type.

The digits are computed exactly, not through floating-point numbers, so very large sizes keep every digit. Answers of 0.1 or more are rounded to four decimal places and smaller ones keep six significant digits. Anything beyond 100 digits or a power of ten above 100 reads "Number too large".

PB to MB table

For coarser units use PB to GB or PB to TB. The MB to GB converter covers the small end, and the Data Units converter converts any pair.

Mistakes to avoid

• Mixing the two systems. 1 MB = 1,000,000,000 PB, but 1 MiB = 1,073,741,824 PiB. A number counted one way must not be compared with one counted the other.
• Confusing bytes and bits. PB with a capital B is bytes; a lowercase b is bits, an eighth the size.
• Reading a labelled capacity as a binary one. Drive and cloud capacities are sold in SI units, while some operating systems report in binary units under the SI names.