size:larger:smaller:Finds messages of a given size, larger or smaller than a threshold.
larger: and smaller: set a threshold, size: a size. Google gives the examples size:1000000 and larger:10M.
larger:10MOpen in Gmail ↗Messages larger than 10M, which means ten megabytes by common usage.
size:1000000Open in Gmail ↗Messages with a size of 1,000,000 (unit not defined by the help page).
size: (bytes? something else?) nor any suffix other than M.Not documented by Google · Gmail Help: search operators