On a clear day in June the terrace has sun 09:00–13:30, about 4.5 hours in total. In short: sun at lunch.
The story of Café Fix
Café Fix at Sankt Eriksgatan 35 opened in 1910, making it one of Stockholm's oldest cafés. It was popular from the start.
Its heyday came in the 1930s and 1940s, when Sankt Eriksgatan was the city's great cinema street. Fix became known as a celebrity café.
The premises were renovated in 2019, giving them a more modern look while keeping old details. Today it serves breakfast, lunch and pastries from early morning.
Sources: Wikipedia: Café Fix · Visit Stockholm: Café Fix · Café Fix
How Stoligt works it out
Every ten minutes we draw a line from each terrace toward the sun and check whether a building or hill is tall enough to block it. Building heights come from OpenStreetMap and ground heights from Lantmäteriet, the Swedish mapping agency. The times assume a clear day, so clouds are not included here. They are on the live map, which shows today's weather.
Trees, parasols and awnings are not in the model, and we don't know exactly where on the pavement the tables stand. Treat the times as an educated guess, often accurate to within ten minutes.