PhDs typically take between three and seven years to complete in the UK.
Thesis examinations happen around two or three months after submission.
Vivas are usually 90 minutes to two-and-a-half hours long.
And all of these things are typical, but not representative of your experience at all. They’re common, but not even close to universal: averages and groupings that don’t respect the variety of experiences in postgraduate research.
In all of these different situations, it’s perhaps best not to focus on how long something is taking – How much longer? When will I be done? When will this be finished? – and instead divert yourself to action. Your thesis submission deadline might be a stressful milestone in some cases, but you don’t have to have that pressure waiting for you in the viva.
Stop watching the clock, start doing something. What can you do to help yourself? Don’t worry about how long your viva might be: what can you do in the viva to help yourself, or what can you do to prepare well?