Jakarta may be the capital of the world's largest Islamic country, but it has underground life of its own. If you're the clubbing type, its nightlife is arguably among the best in Asia. From the upscale X-Lounge to the seediest discos like Stadium, Jakarta caters to all kinds of clubbers, but bring a friend if you decide to brave the seedier joints though they tend to have the best DJs. Fans of live music, on the other hand, are largely out of luck if they go to budget bars, at least unless they're into Indonesian pop.
When out and about, note that Jakarta has a fairly high number of prostitutes, known in local parlance as ayam lit. "chicken", so much so that much of the female clientele of some respectable bars operated by five-star hotels, etc is on the take.
A nightlife district popular among expats is Blok M in South Jakarta, or more specifically the single lane of Jl. Palatehan 1 just north of the bus terminal, packed with pubs and bars geared squarely towards single male Western visitors. While lacking the bikini-clad go-go dancers of Patpong, the meat market atmosphere is much the same with poor country girls turned pro. Blok M is now easily accessible as the southern terminus of BRT Line 1. For a more off-the-beaten track experience, head a few blocks south to Jl. Melawai 6 opposite Plaza Blok M, Jakarta's de-facto Little Japan with lots of Japanese restaurants, bars and what else? karaoke joints.
To hang out where Indonesia's young, rich and beautiful do, head to Plaza Indonesia's EX annex, packed full of trendy clubs and bars including Jakarta's Hard Rock Cafe. Plaza Senayan's Arcadia annex attempts to duplicate the concept, but with more of an emphasis on fine dining. The Kemang area in southern Jakarta is popular with expats and locals alike. It has numerous places to eat, drink and dance.
The Kota area in northern Jakarta is the oldest part of town with numerous colonial buildings still dominating the area. It is also considered to be the seediest part of town after midnight. Most karaoke bars and 'health' clubs there are in fact brothels who mostly cater to local Jakartans. Even regular discos such as Stadium and Crown have special areas designated for prostitutes. Other notable establishments in this area are Malioboro and Club 36 which should not be missed. This part of town has a large ethnic Chinese population who also dominate the clubbing scene there.
The bulk of the clubbing scene is spread throughout Jakarta however, most usually found in office buildings or hotels. A help of an experienced local with finding these places is recommended. Do note that nightlife in Jakarta tends to be pricey for local standards.
In general, dress codes are strictly enforced in Jakarta: no shorts, no slippers. During the month of Ramadhan, all nightlife ends at midnight and some operations close for the entire month.