Please be aware that Johannesburg has multiple airports and that these results are for all airports serving the city.
The best day to arrive at Johannesburg is Wednesday and it would be best to avoid Saturday, as prices are on average 336.19% higher than on Wednesday. (Average prices, based on 470 datapoints.)
At Johannesburg the most flights depart around 08:00. (Hourly flights, based on 298 datapoints.)
From Johannesburg it is on average the cheapest to fly to Durban and to Cape Town. (Average prices, based on 291 datapoints.)
From Johannesburg most of the flights depart to Durban, second best connected from Johannesburg is Cape Town. (Daily flights, based on 87 datapoints.)