Khetha indlela yokuguqula. Uma ufaka isitembu sesikhathi, khetha ngokucacile amasekhondi noma amamilisekhondi. Amasekhondi angaba nezindawo zedesimali ezifika kwezintathu; amamilisekhondi kufanele abe yinombolo ephelele. Faka usuku ngefomethi ethi YYYY-MM-DDTHH:mm:ss; lungaba nengxenye yesekhondi enezinombolo eyodwa kuya kwezintathu ngemva kwechashazi futhi kufanele lugcine ngo-Z noma ±HH:mm. Umphumela ubonisa usuku lwe-UTC, amasekhondi namamilisekhondi ndawonye.
Faka into eyodwa emugqeni ngamunye, kuze kube yimigqa engu-500. Umugqa ngamunye ubonisa umphumela noma iphutha; nemigqa engenalutho iba nephutha. Usuku lwendawo lusebenzisa izoni yesikhathi nemithetho yokonga ukukhanya kwemini yedivayisi. Usuku olufakwayo kusadingeka lube no-Z noma umehluko wezoni yesikhathi ocacile.
Isitembu sesikhathi esingu-0 sihambisana no-1970-01-01T00:00:00.000Z; -1 isekhondi sisho isekhondi elilodwa ngaphambi kwalokho. Izingxenye zesekhondi ezingaphansi kuka-zero zigcinwa njengoba zinjalo, ngaphandle kokusikwa ziye ku-zero. Izinsuku ezingekho, amasekhondi angeziwe okulungisa isikhathi, nezinsuku ezingenazoni yesikhathi azamukelwa. Unyaka wosuku olufakwayo kufanele ube nezinombolo ezine; umkhawulo wesitembu sesikhathi ngu-8640000000000000 amamilisekhondi ohlangothini oluhle noma olubi. Isikhathi samanje sivela ewashini lale divayisi.