muck around vs muck about

muck around and muck about both are verbs.

Word	Noun	Adjective	Verb	Adverb
muck around	No	No	Yes	No
muck about	No	No	Yes	No

As verbs, muck around and muck about are synonyms defined as:

muck around and muck about: do random, unplanned work or activities or spend time idly

Other synonyms of muck around include mess around, monkey, monkey around, potter, putter, tinker.

muck around (verb)	muck about (verb)
do random, unplanned work or activities or spend time idly	do random, unplanned work or activities or spend time idly