Rio de Janeiro to Acton, MA: time difference
Acton, MA is 1 h behind Rio de Janeiro. Live clocks for both, the working hours they share, and how each one sits against your own time.
Your time
One day, 2 clocks
Drag along the band to read any hour in every place at once.
Rio de Janeiro 05:36 5:36 AM Acton, MA 04:36 4:36 AM You –:–
05:36 5:36 AM
Brasilia Standard Time · UTC-3
☀️ 05:26 · 🌙 17:55
04:36 4:36 AM
Eastern Daylight Time · UTC-4
☀️ 06:53 · 🌙 18:13
·
−1 h
Acton, MA is 1 h behind Rio de Janeiro.
When you, Rio de Janeiro and Acton, MA are all at the desk
Pick the working hours below – the window every location shares appears once your time zone is known.
Working hours
🇧🇷 Rio de Janeiro
0 12 AM 1 1 AM 2 2 AM 3 3 AM 4 4 AM 5 5 AM 6 6 AM 7 7 AM 8 8 AM 9 9 AM 10 10 AM 11 11 AM 12 12 PM 13 1 PM 14 2 PM 15 3 PM 16 4 PM 17 5 PM 18 6 PM 19 7 PM 20 8 PM 21 9 PM 22 10 PM 23 11 PM
🇺🇸 Acton, MA
23 11 PM 0 12 AM 1 1 AM 2 2 AM 3 3 AM 4 4 AM 5 5 AM 6 6 AM 7 7 AM 8 8 AM 9 9 AM 10 10 AM 11 11 AM 12 12 PM 13 1 PM 14 2 PM 15 3 PM 16 4 PM 17 5 PM 18 6 PM 19 7 PM 20 8 PM 21 9 PM 22 10 PM
📍 Your time
- Asleep
- Early
- Working hours
- Evening
- Both working
- Right now
Time zones side by side
| Detail | 🇧🇷 Rio de Janeiro | 🇺🇸 Acton, MA |
|---|---|---|
| Local time | 05:36 | 04:36 |
| Local date | Saturday, October 10, 2026 | Saturday, October 10, 2026 |
| Time zone | Brasilia Standard Time | Eastern Daylight Time |
| UTC offset | UTC-3 | UTC-4 |
| Offset from Rio de Janeiro | — | −1 h |
| IANA zone | America/Sao Paulo | America/New York |
| Daylight saving | Not observed | On summer time → UTC-5, Nov 1, 01:00 |
| Sunrise | 05:26 | 06:53 |
| Sunset | 17:55 | 18:13 |
| Daylight | 12 h 30 min | 11 h 20 min |
| People on this clock | 6,211,223 | 7,596 |
Compare Rio de Janeiro with another city
More comparisons with Rio de Janeiro: the time zones next to it and the far side of the clock.
Nearby time zones
Big time differences
Rio de Janeiro and Acton, MA: common questions
How many hours behind Rio de Janeiro is Acton, MA?
The clocks in Acton are 1 hour behind those in Rio de Janeiro (UTC−4 and UTC−3).
What time is it in Acton, MA, when it is 9:00 AM in Rio de Janeiro?
When it is 9:00 AM in Rio de Janeiro, it is 8:00 AM in Acton.
What time is it in Acton, MA, at the end of the working day in Rio de Janeiro?
The working day in Rio de Janeiro ends at 6:00 PM; in Acton it is 5:00 PM at that moment.
When do working hours in Rio de Janeiro and in Acton, MA, overlap?
Working hours (9:00 AM–6:00 PM) overlap from 10:00 AM to 6:00 PM in Rio de Janeiro, which is 9:00 AM to 5:00 PM in Acton.
When does the date change in Acton, MA, compared with Rio de Janeiro?
The new day starts in Acton later: until 1:00 AM in Rio de Janeiro, it is still the previous day there. From 11:00 PM in Acton, Rio de Janeiro is already on the next day.
Is the time difference between Rio de Janeiro and Acton, MA, the same all year?
No. Only Acton switches to summer time, so the gap changes twice a year. From November 1, 2026, Acton will be 2 hours behind Rio de Janeiro.
