diff --git a/src/randomProcesses/fft/fft.C b/src/randomProcesses/fft/fft.C
index 660079d6bf..67d13fd04d 100644
--- a/src/randomProcesses/fft/fft.C
+++ b/src/randomProcesses/fft/fft.C
@@ -48,8 +48,9 @@ void fft::transform
 {
     forAll(nn, idim)
     {
-        scalar pow2 = log(scalar(nn[idim]))/log(scalar(2));
-        if ((pow2 - int(pow2 + 0.5)) > SMALL)
+        // Check for power of two
+        unsigned int dimCount = nn[idim];
+        if (!dimCount || (dimCount & (dimCount - 1)))
         {
             FatalErrorIn
             (