Risk appetite also revived, providing more support to the regional currencies, with upbeat corporate results helping alleviate market sentiment, which was hit by S&P's warning on US Credit ratings and worries about Greece's debt problems.
The regional foreign exchange authorities, including central banks of Malaysia and Thailand, were spotted buying dollars to cap their gains, but they lowered levels of dollar bids rather than stick to specific levels, dealers said.
"Central banks are trying to slow the pace of appreciation rather than reversing that, so Asian currencies are likely to be bullish in the near-term, with inflation to remain the key concern," said Ho Woei Chen, an economist at United Overseas Bank in Singapore.
South Korea and Indonesia are more willing to allow for currency appreciation as they fight the inflationary pressure, Ho said.
Earlier, China's central bank fixed the yuan's mid-point at a record high and the Chinese currency hit another record high against the dollar while officials lamented the impact of imported inflation.
Emerging Asian currencies have been boosted by expectations that policymakers will allow their currencies to rise more to contain rising prices, along with inflows to the regional stocks and bonds.
Higher stocks aided by strong corporate results are expected to allure more funds to emerging Asia, analysts said.
"A jump in stocks on firm results will double investors' desire to use liquidity and power Asian currencies more," said Jeong My-young, a currency strategist at Samsung Futures in Seoul.
WON
The won matched a 31-month high against the dollar during the local trade on strong demand from hedge funds and exporters, which helped local interbank speculators build up dollar-short positions.
The South Korean currency strengthened to as firm as 1,082.0 versus the greenback, the intraday high on April 8, the strongest since Sept 2008.
State-run importers and importers bought dollars while some suspected the foreign exchange authorities of purchasing the US currency, boosting caution over intervention.
But those dollar bids just slowed down the won's strength, dealers said.
"Sizeable importers' deals failed to lift USD/KRW and everybody is waiting for the authorities. I wish I could see them soon to enter fresh shorts at higher levels," said a senior foreign bank dealer in Seoul.
SINGAPORE DOLLAR
The Singapore dollar hit a record low of 1.2400 per the US dollar helped by demand from interbank speculators and funds.
Monetary Authority of Singapore was not spotted buying the greenback, dealers said.
The city-state's currency gave up some of earlier gains on option-related supplies, but it is seen rising again.
RINGGIT
The ringgit strengthened to near 14-year high against the dollar on interbank speculators and funds.
The Malaysian central banks bought an estimated $500 million to stem the country's currency, dealers said. But it lowered dollar bids step by step.
The ringgit gained to as firm as 3.0130, a notch of 3.0110 hit on April 14, the strongest since Oct 1997.
The baht broke through 30.00 per dollar, which the central bank had defended earlier, after it said it would closely monitor inflation and take action as appropriate.
A Bangkok-based dealer said the central bank might pull out dollar bids after it raised interest rates.
Earlier, the Bank of Thailand had been spotted buying dollars at 30.02 and 30.00, dealers said.
Thio Chin Loo, a currency strategist with BNP Paribas in Singapore said the Thai currency would rise more slowly than its peers with a forecast of 29.50 by end-2011, citing political risks and slower growth.
The baht has risen 0.67 percent versus the greenback so far this year, becoming the worst performer among emerging Asian currencies.