Please be aware that Jakarta and Tokyo has multiple airports and that these results are for all airports serving the city.
The best month to fly between Jakarta and Tokyo is January and the most expensive month to fly is December. (Average prices, based on 10880 datapoints.)
The best day to arrive at Jakarta is Tuesday and it would be best to avoid Saturday, as prices are on average 26.05% higher than on Tuesday. (Average prices, based on 8071 datapoints.)