If Possible, you'll want to enable 3-5h of transit time in Johannesburg, so you have enough time for you to capture your connecting flight. Transiting in Johannesburg is rather straightforward; simply just follow the indicators for ‘Worldwide Transit’. The flight from Johannesburg to Harare normally takes about 1h 30m. The https://www.theluxurybooking.co.uk/flights-to-zimbabwe-from-london/