diff --git a/src/crypto/ecdsa/ecdsa.go b/src/crypto/ecdsa/ecdsa.go
index 219436935f..282596d2d2 100644
--- a/src/crypto/ecdsa/ecdsa.go
+++ b/src/crypto/ecdsa/ecdsa.go
@@ -200,12 +200,8 @@ var errZeroParam = errors.New("zero parameter")
 func Sign(rand io.Reader, priv *PrivateKey, hash []byte) (r, s *big.Int, err error) {
 	randutil.MaybeReadByte(rand)
 
-	// Get min(log2(q) / 2, 256) bits of entropy from rand.
-	entropylen := (priv.Curve.Params().BitSize + 7) / 16
-	if entropylen > 32 {
-		entropylen = 32
-	}
-	entropy := make([]byte, entropylen)
+	// Get 256 bits of entropy from rand.
+	entropy := make([]byte, 32)
 	_, err = io.ReadFull(rand, entropy)
 	if err != nil {
 		return