diff --git a/fs/filter.go b/fs/filter.go
index 25f4db27f..a8ea27b8d 100644
--- a/fs/filter.go
+++ b/fs/filter.go
@@ -28,8 +28,8 @@ var (
 	filesFrom      = pflag.StringP("files-from", "", "", "Read list of source-file names from file")
 	minAge         = pflag.StringP("min-age", "", "", "Don't transfer any file younger than this in s or suffix ms|s|m|h|d|w|M|y")
 	maxAge         = pflag.StringP("max-age", "", "", "Don't transfer any file older than this in s or suffix ms|s|m|h|d|w|M|y")
-	minSize        SizeSuffix
-	maxSize        SizeSuffix
+	minSize        = SizeSuffix(-1)
+	maxSize        = SizeSuffix(-1)
 	dumpFilters    = pflag.BoolP("dump-filters", "", false, "Dump the filters to the output")
 	//cvsExclude     = pflag.BoolP("cvs-exclude", "C", false, "Exclude files in the same way CVS does")
 )
@@ -342,8 +342,8 @@ func (f *Filter) InActive() bool {
 	return (f.files == nil &&
 		f.ModTimeFrom.IsZero() &&
 		f.ModTimeTo.IsZero() &&
-		f.MinSize == 0 &&
-		f.MaxSize == 0 &&
+		f.MinSize < 0 &&
+		f.MaxSize < 0 &&
 		f.fileRules.len() == 0 &&
 		f.dirRules.len() == 0)
 }
@@ -390,10 +390,10 @@ func (f *Filter) Include(remote string, size int64, modTime time.Time) bool {
 	if !f.ModTimeTo.IsZero() && modTime.After(f.ModTimeTo) {
 		return false
 	}
-	if f.MinSize != 0 && size < f.MinSize {
+	if f.MinSize >= 0 && size < f.MinSize {
 		return false
 	}
-	if f.MaxSize != 0 && size > f.MaxSize {
+	if f.MaxSize >= 0 && size > f.MaxSize {
 		return false
 	}
 	return f.includeRemote(remote)
diff --git a/fs/filter_test.go b/fs/filter_test.go
index 9159e7fba..3838919f1 100644
--- a/fs/filter_test.go
+++ b/fs/filter_test.go
@@ -49,8 +49,8 @@ func TestNewFilterDefault(t *testing.T) {
 	f, err := NewFilter()
 	require.NoError(t, err)
 	assert.False(t, f.DeleteExcluded)
-	assert.Equal(t, int64(0), f.MinSize)
-	assert.Equal(t, int64(0), f.MaxSize)
+	assert.Equal(t, int64(-1), f.MinSize)
+	assert.Equal(t, int64(-1), f.MaxSize)
 	assert.Len(t, f.fileRules.rules, 0)
 	assert.Len(t, f.dirRules.rules, 0)
 	assert.Nil(t, f.files)
@@ -109,8 +109,8 @@ func TestNewFilterFull(t *testing.T) {
 		rm(*excludeFrom)
 		rm(*includeFrom)
 		rm(*filesFrom)
-		minSize = 0
-		maxSize = 0
+		minSize = -1
+		maxSize = -1
 		deleteExcluded = &isFalse
 		filterRule = &emptyString
 		filterFrom = &emptyString
@@ -352,7 +352,6 @@ func TestNewFilterMatches(t *testing.T) {
 		{"a/one.png", 101, 0, false},
 		{"unicorn", 99, 0, false},
 	})
-	t.Log(f.DumpFilters())
 	testDirInclude(t, f, []includeDirTest{
 		{"sausage1", false},
 		{"sausage2", false},
diff --git a/fs/operations_test.go b/fs/operations_test.go
index 83e71306f..b4f850851 100644
--- a/fs/operations_test.go
+++ b/fs/operations_test.go
@@ -709,7 +709,7 @@ func TestSyncWithExclude(t *testing.T) {
 
 	fs.Config.Filter.MaxSize = 40
 	defer func() {
-		fs.Config.Filter.MaxSize = 0
+		fs.Config.Filter.MaxSize = -1
 	}()
 
 	fs.Stats.ResetCounters()
@@ -742,7 +742,7 @@ func TestSyncWithExcludeAndDeleteExcluded(t *testing.T) {
 	fs.Config.Filter.MaxSize = 40
 	fs.Config.Filter.DeleteExcluded = true
 	defer func() {
-		fs.Config.Filter.MaxSize = 0
+		fs.Config.Filter.MaxSize = -1
 		fs.Config.Filter.DeleteExcluded = false
 	}()
 
@@ -999,7 +999,7 @@ func TestDelete(t *testing.T) {
 
 	fs.Config.Filter.MaxSize = 60
 	defer func() {
-		fs.Config.Filter.MaxSize = 0
+		fs.Config.Filter.MaxSize = -1
 	}()
 
 	err := fs.Delete(r.fremote)