diff --git a/Data/BloomFilter/Easy.hs b/Data/BloomFilter/Easy.hs
--- a/Data/BloomFilter/Easy.hs
+++ b/Data/BloomFilter/Easy.hs
@@ -68,7 +68,7 @@
         (bits :: Double, hashes :: Double) =
             minimum [((-k) * cap / log (1 - (errRate ** (1 / k))), k)
                      | k <- [1..100]]
-    in (nextPowerOfTwo (round bits), round hashes)
+    in (nextPowerOfTwo (ceiling bits), truncate hashes)
   where fatal = error . ("Data.BloomFilter.Util.suggestSizing: " ++)
 
 -- $example
diff --git a/bloomfilter.cabal b/bloomfilter.cabal
--- a/bloomfilter.cabal
+++ b/bloomfilter.cabal
@@ -1,5 +1,5 @@
 name:            bloomfilter
-version:         1.2.0
+version:         1.2.1
 license:         BSD3
 license-file:    LICENSE
 author:          Bryan O'Sullivan <bos@serpentine.com>