500 (D) was a leap year starting on Saturday of the Julian calendar, the 500th year of the Common Era (CE) and Anno Domini (AD) designations, the 500th year of the 1st millennium, the 100th and last year of the 5th century, and the 1st year of the 500s decade. As of the start of 500, the Gregorian calendar was 1 day ahead of the Julian calendar, which was the dominant calendar of the time.

Millennium: 1st millennium
Centuries: 4th century5th century6th century
Decades: 470s  480s  490s  – 500s –  510s  520s  530s
Years: 497 498 499500501 502 503
500 in other calendars
Gregorian calendar500
Ab urbe condita1253
Assyrian calendar5250
Balinese saka calendar421–422
Bengali calendar−93
Berber calendar1450
Buddhist calendar1044
Burmese calendar−138
Byzantine calendar6008–6009
Chinese calendar己卯(Earth Rabbit)
3196 or 3136
    — to —
庚辰年 (Metal Dragon)
3197 or 3137
Coptic calendar216–217
Discordian calendar1666
Ethiopian calendar492–493
Hebrew calendar4260–4261
Hindu calendars
 - Vikram Samvat556–557
 - Shaka Samvat421–422
 - Kali Yuga3600–3601
Holocene calendar10500
Iranian calendar122 BP – 121 BP
Islamic calendar126 BH – 125 BH
Javanese calendar386–387
Julian calendar500
Korean calendar2833
Minguo calendar1412 before ROC
Nanakshahi calendar−968
Seleucid era811/812 AG
Thai solar calendar1042–1043
Tibetan calendar阴土兔年
(female Earth-Rabbit)
626 or 245 or −527
    — to —
(male Iron-Dragon)
627 or 246 or −526

It is one of only seven years to use just one Roman numeral. The seven are 1 AD (I), 5 AD (V), 10 AD (X), 50 AD (L), 100 AD (C), 500 AD (D), and 1000 AD (M).