On arrival
- Santo Domingo and San Juan are in the same time zone — no jet lag adjustment needed.
Jet lag plan
Santo Domingo and San Juan share the same time zone.
About 403 km due east · approximately 1.5-hour non-stop flight · a short-haul flight.
The route from Santo Domingo, Dominican Republic to San Juan, Puerto Rico covers roughly 403 kilometres in a due east direction. At standard jet cruise speed plus a one-hour allowance for taxi, climb, and descent, a non-stop flight takes about 1.5 hours. Both cities sit in the northern hemisphere, so the seasonal direction of daylight (longer days in June, shorter in December) matches between origin and destination.
Santo Domingo is in the tropics, so day length varies only slightly across the year. Light cues for the circadian system stay strong year-round. San Juan is in the tropics, so day length varies only slightly across the year. Light cues for the circadian system stay strong year-round.
Standard 09:00–18:00 working hours at both ends of this route overlap by approximately 9 hours. In Santo Domingo that window runs 09:00 to 18:00; in San Juan it is 09:00 to 18:00. This is the realistic window for live meetings, customer calls, or pair work without forcing either end out of normal hours.
Neither city observes daylight saving time, so the hour offset on this route is fixed year-round. This makes recurring schedules and calendar invites with collaborators on the other end safer than for DST-observing pairs.
The great-circle distance from Santo Domingo to San Juan is about 403 kilometres. A typical non-stop flight takes around 1.5 hours at standard cruise speed; routes with connections add two to four hours.
Santo Domingo and San Juan share the same time zone, so there is no clock offset on this route.
No circadian shift is required between these two cities.
For a shift of 0 hours, melatonin offers little benefit beyond what consistent light exposure already provides. The Cochrane review on jet-lag melatonin shows the strongest effects on shifts of five hours or more.
For a shift under two hours, pre-trip adjustment is usually not worth the effort.
Chronotype does not affect adjustment on a same-time-zone route.