San Juan to Dublin Time
AST to GMT Converter — 9 AM AST is 1:00 PM GMT
San Juan is 4 hours behind Dublin. Convert any time between San Juan (AST) and Dublin (GMT/IST) instantly.
San Juan
Puerto Rico
Dublin
Ireland
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San Juan to Dublin Time Conversion Table
| San Juan (AST) | Dublin (GMT) |
|---|---|
| 12:00 AM | 5:00 AM |
| 2:00 AM | 7:00 AM |
| 4:00 AM | 9:00 AM |
| 6:00 AM | 11:00 AM |
| 8:00 AM | 1:00 PM |
| 10:00 AM | 3:00 PM |
| 12:00 PM | 5:00 PM |
| 2:00 PM | 7:00 PM |
| 4:00 PM | 9:00 PM |
| 6:00 PM | 11:00 PM |
| 8:00 PM | 1:00 AM |
| 10:00 PM | 3:00 AM |
San Juan & Dublin — Business & Scheduling Guide
San Juan (Puerto Rico) is a US territory with pharmaceutical and tech manufacturing, with key industries in pharmaceuticals, medical devices, electronics, and tourism. Dublin is the European tech HQ capital, known for European headquarters for Google, Meta, Apple, LinkedIn, and a booming fintech scene. With a 4-hour time difference, professionals frequently schedule cross-border calls between these two cities for international trade, remote team collaboration, and client meetings.
Scheduling Meetings Between San Juan and Dublin
The 4-hour difference between San Juan and Dublin requires careful scheduling. The best overlap window is typically 2–4 hours when both cities are within working hours. Puerto Rican business hours are typically 8 AM–5 PM, with a bilingual (English/Spanish) workforce. Irish business hours are typically 9 AM–5:30 PM, with Dublin hosting European HQs for Google, Meta, Apple, and many others. Teams often designate specific "overlap hours" for real-time collaboration and use asynchronous communication (Slack, email, recorded video) for the rest of the day.
Daylight Saving Time Considerations
Dublin observes Daylight Saving Time (GMT/IST), while San Juan stays on AST year-round. When Dublin switches to daylight time, the effective time difference shifts by 1 hour. This typically happens in spring and fall, and the exact dates vary by country. If you have recurring cross-timezone meetings, recalculate the schedule after each DST transition.
Collaboration Tools & Workflow
The 4-hour gap between San Juan and Dublin means teams get roughly half a day of overlapping work hours. Successful cross-timezone teams typically batch synchronous activities (standups, reviews, planning) into the overlap window and reserve solo deep work for non-overlapping hours. Tools like Loom for async video updates, Slack with status indicators showing each team's local time, and shared Notion docs help bridge the gap. Many teams adopt a "follow-the-sun" workflow where handoffs happen at the edges of each team's workday.
Remote Work Between San Juan & Dublin
San Juan, a key city in Puerto Rico, and Dublin, European headquarters for Google, are well-connected for remote work. With a manageable 4-hour time difference, distributed teams can maintain a near-synchronous workflow. Both cities have strong internet infrastructure, coworking spaces, and established remote work cultures. For freelancers and remote workers, this time zone pairing is ideal — you can serve clients in Dublin from San Juan (or vice versa) without disrupting your standard workday.
AST to GMT — Quick Reference
AST (AST) stands for the timezone used in San Juan, Puerto Rico (UTC-4). GMT (GMT/IST) is the timezone used in Dublin, Ireland (UTC+0). San Juan is 4 hours behind Dublin.
To convert AST to GMT, add 4 hours to AST time. For example, AST 9:00 AM = GMT 1:00 PM.
Key Facts
- •Time difference: San Juan (UTC-4) is 4 hours behind Dublin (UTC+0).
- •Daylight Saving Time: San Juan does not observe DST (AST). Dublin observes DST (GMT/IST).
- •Regions: San Juan is located in Puerto Rico and uses the AST time zone. Dublin is located in Ireland and uses the GMT/IST time zone.
- •Best time to call: The best time to call between San Juan and Dublin is 9:00 AM to 12:00 PM in San Juan time, when both cities have overlapping standard working hours.
Frequently Asked Questions
What is the time difference between San Juan and Dublin?
San Juan is 4 hours behind Dublin.
What time is it in Dublin when it's 9 AM in San Juan?
When it's 9:00 AM in San Juan, it is 1:00 PM in Dublin.
What time is 9 PM AST in GMT?
9 PM AST (San Juan time) is 1:00 AM GMT (Dublin time). This is a common time people check when scheduling evening calls across these two time zones.
When is the best time to schedule a meeting between San Juan and Dublin?
The best time to schedule a meeting is between 9:00 AM to 12:00 PM in San Juan time, when both cities are within standard working hours (9 AM – 5 PM). This gives you the maximum overlap window for real-time collaboration.
How do I convert AST to GMT?
AST (AST) is the timezone for San Juan, Puerto Rico (UTC-4). GMT (GMT/IST) is the timezone for Dublin, Ireland (UTC+0). San Juan is 4 hours behind Dublin. Quick examples: 9 AM AST = 1:00 PM GMT, 12 PM AST = 4:00 PM GMT, 3 PM AST = 7:00 PM GMT, 6 PM AST = 10:00 PM GMT.
Is San Juan ahead of or behind Dublin?
San Juan is 4 hours behind Dublin. When it's noon in San Juan, it's 4:00 PM in Dublin.
Does San Juan or Dublin change clocks for Daylight Saving Time?
No, San Juan does not observe DST — it stays on AST year-round. Dublin observes DST and switches between GMT/IST. Because only one city observes DST, the time difference shifts by 1 hour during transition periods (typically March/April and October/November).
What time is noon in San Juan in Dublin time?
When it is 12:00 PM (noon) in San Juan (AST), it is 4:00 PM in Dublin (GMT). This is often a popular time for scheduling lunch-hour calls across the San Juan–Dublin corridor.
What are the overlapping work hours between San Juan and Dublin?
The overlapping work hours between San Juan and Dublin are approximately 9:00 AM to 12:00 PM in San Juan time, when both cities are within the standard 9 AM–5 PM workday. This is the ideal window for meetings, pair programming, and real-time collaboration.
What timezone is San Juan in?
San Juan is in the AST time zone (UTC-4). It is located in Puerto Rico. San Juan does not observe Daylight Saving Time.
What timezone is Dublin in?
Dublin is in the GMT/IST time zone (UTC+0). It is located in Ireland. Dublin observes Daylight Saving Time, switching between GMT/IST.
How do I schedule a call between San Juan and Dublin?
To schedule a call between San Juan and Dublin, aim for the overlapping window of 9:00 AM to 12:00 PM in San Juan time. Use Google Calendar or Calendly with both time zones visible, share the meeting invite with the GMT time clearly noted, and always double-check the time difference — especially during DST transitions. Pro tip: include both local times in the calendar invite title (e.g., "Sync — 10 AM AST / 2:00 PM GMT").
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