But crown buying accelerated after the Swiss National Bank scrapped the franc's cap against the euro. It also cut interest rates to -0.75 percent. Some analysts think the Danish central bank may have more cuts up its sleeve.
"The objective is to push down money market rates and make it less attractive to hold crowns," a bank spokesman said. "We expect a reaction so we don't need to intervene and the crown will weaken."
The crown, whose daily movements are generally tiny, weakened to 7.4452 per euro from 7.4440 before the cut, then recovered to trade at 7.4438.
Handelsbanken Chief Economist Jes Asmussen estimated the central bank had spent a record 100 billion crowns in January defending the peg to the euro.
Read MoreSNB: Central bankers have 'a license to lie'
Under the Exchange Rate Mechanism, Denmark agreed to keep the crown in a corridor of 2.25 percent either side of of 7.46038 crowns to the euro. In practice, it has maintained a tighter range of 0.50 percent either side.
Immediately after the Swiss move, some in the market speculated the Danes would be next to drop their fixed currency policy, despite its popularity across the political and business spectrum.
Helge Pedersen, Global Chief Economist at Nordea Bank, said the Danish National Bank had in effect underscored Denmarks' "unwavering" commitment to the policy.
Read MoreTrading ECB buying bombshell—1 week later
Follow us on Twitter: @CNBCWorld