The rupee firmed 6 paise at 63.85 against the dollar in opening trade on Friday, maintaining its upward trend for the fourth straight day on sustained selling of the US currency by exporters and banks amid a higher opening in the domestic equity market.
The dollar slipped to a three-year low against a basket of currencies today.
Forex dealers said the greenback is headed for its biggest weekly loss in two years.
A higher opening in the domestic equity market gave the uptrend some momentum, they added.
The benchmark BSE Sensex rose 196.39 points, or 0.57 per cent, to 34,493.86 in early session today.
Yesterday, the domestic unit ended higher by 18 paise against the dollar at 63.91.
Meanwhile, the dollar was trading flat against the yen after slipping to 106.020, its lowest level in 15 months.