gives the number of bytes currently being used to store all data in the current Wolfram Language kernel session.
gives the number of bytes used in the Wolfram System front end.
MemoryInUse
gives the number of bytes currently being used to store all data in the current Wolfram Language kernel session.
gives the number of bytes used in the Wolfram System front end.
Examples
open all close allBasic Examples (2)
Possible Issues (1)
MemoryInUse[]Range[10 ^ 6];Even though there is no visible output, the result is still assigned to Out[2], so memory is used:
MemoryInUse[]Add an expression after the ; to prevent the large result being assigned to Out[4]:
Range[10 ^ 6];NoneMemoryInUse[]Tech Notes
History
Introduced in 1988 (1.0) | Updated in 2007 (6.0)
Text
Wolfram Research (1988), MemoryInUse, Wolfram Language function, https://reference.wolfram.com/language/ref/MemoryInUse.html (updated 2007).
CMS
Wolfram Language. 1988. "MemoryInUse." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2007. https://reference.wolfram.com/language/ref/MemoryInUse.html.
APA
Wolfram Language. (1988). MemoryInUse. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/MemoryInUse.html
BibTeX
@misc{reference.wolfram_2026_memoryinuse, author="Wolfram Research", title="{MemoryInUse}", year="2007", howpublished="\url{https://reference.wolfram.com/language/ref/MemoryInUse.html}", note=[Accessed: 13-June-2026]}
BibLaTeX
@online{reference.wolfram_2026_memoryinuse, organization={Wolfram Research}, title={MemoryInUse}, year={2007}, url={https://reference.wolfram.com/language/ref/MemoryInUse.html}, note=[Accessed: 13-June-2026]}