Yes, it is free to tour, I didn't climb the tower, but the church and grounds are free.
It's a church, so of course it is free (though gifts for the upkeep are always appreciated). You only have to pay a symbolic fee should you wish to climb the tower. But there's a magnificent view from the platform next to the Münster already.
You can enter the building for free. It is a nominal fee (3-5 CHF) to climb the towers.
It was 2.5 euro last August
little more than 3 £ (5 CHF)
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