I came across this on Wikipedia:

As expected for a common occurrence, laughter is frequently depicted in books and cartoons.

Language	How written	Nuance
German	hahaha	(normal)
	hnhnhn hmhmhm chrchrchr	(giggle)
	muhaha ahehe uhaha	(sardonic)
	höhöhö	(ironic)
Hungarian	hahaha	(classical; the length of it depends on how funny we find the thing we are laughing about)
	ha… ha… ha…	(sarcastic)
	hehehe	(can be a bit malevolent, especially if it is combined with raised eyebrows and a little smile)
	hihihi	(giggle)
	ho-ho-ho-hóóó	(a la Santa Claus)
	kac-kac	(ironic)
Indonesian	huehehehe	(cute way of laughter)
	bwahahaha	(more satisfied way of laughter)
Malaysian	Kahkahkah
Polish	hehe	(casual way of expressing laughter)
	haha	(more crude; can be ironic)
Russian	ха-ха-ха!	(hahaha)
	хи-хи	(heehee – giggle)
	хе-хе	(hehe, very mean laughter)
Serbian	ahahaha	(loud laughter)
	he, he, he	(can be a bit meanish)
	hi, hi, hi	(giggling)
	ho, ho, ho	(rare, Santa Claus laughter)
Spanish (Venezuela)	ja ja ja	(Usual laugh)
	je je je	(Mischievous little laughter)
	ji ji ji	(Giggle)
	jo jo jo	(San Nicolás -Santa Claus- laugh)
	jú jú jú (In a high pitch)	(mean laugh after a prank)
	ujú ja ja ja ja ja jaaaaaa… ñaca-ñaca	(Evil laugh)
Swedish	haha	(any plain laughter)
	hehe	(more hissing)
	hihi	(giggling)
	hoho	(Santa Claus style)
	höhö	(ironic)
	moahaha	(the evil one)
	eheh	(embarrassed)
Turkish	hahaha	(very typical laughter, it’s usually triple ‘ha’, not double)
	hehehe	(sound a bit more ‘polite’ than hahaha)
	ha… ha… ha…	(sarcastic)
	hihihi	(giggling)
	ahahaha	(got popular after a TV series character who used to laugh this way)
	ehehehe	(same as hehehe)
	eki eki	(used in comics, especially as the oldie way laughter)
	keh keh/kah kah	(sneaky-ish lughter)
	muhaha	(evil laughter)
	nihaha	(evil laughter)
	puhaha	(used if it’s too amusing)
	uhaha	(almost like puhaha)
	zuhaha	(almost like puhaha)