diff --git a/bar_filler.go b/bar_filler.go
index 2a7d0e8..d26f4a9 100644
--- a/bar_filler.go
+++ b/bar_filler.go
@@ -1,8 +1,9 @@
 package mpb
 
 import (
+	"bytes"
 	"io"
-	"strings"
+	"unicode/utf8"
 
 	"github.com/vbauerster/mpb/v4/decor"
 	"github.com/vbauerster/mpb/v4/internal"
@@ -17,54 +18,67 @@
 	rRefill
 )
 
-var defaultBarStyle = []rune("[=>-]+")
+var defaultBarStyle = "[=>-]+"
 
 type barFiller struct {
-	format []rune
+	format [][]byte
 	rup    int
+}
+
+func newDefaultBarFiller() Filler {
+	bf := &barFiller{
+		format: make([][]byte, utf8.RuneCountInString(defaultBarStyle)),
+	}
+	bf.setStyle(defaultBarStyle)
+	return bf
+}
+
+func (s *barFiller) setStyle(style string) {
+	if !utf8.ValidString(style) {
+		style = defaultBarStyle
+	}
+	src := make([][]byte, 0, utf8.RuneCountInString(style))
+	for _, r := range style {
+		src = append(src, []byte(string(r)))
+	}
+	copy(s.format, src)
 }
 
 func (s *barFiller) Fill(w io.Writer, width int, stat *decor.Statistics) {
 
-	str := string(s.format[rLeft])
+	b := s.format[rLeft]
 
 	// don't count rLeft and rRight [brackets]
 	width -= 2
 
-	if width <= 2 {
-		io.WriteString(w, str+string(s.format[rRight]))
+	if width < 2 {
+		return
+	} else if width == 2 {
+		w.Write(append(b, s.format[rRight]...))
 		return
 	}
 
-	progressWidth := internal.Percentage(stat.Total, stat.Current, int64(width))
-	needTip := progressWidth < int64(width) && progressWidth > 0
+	cwidth := internal.Percentage(stat.Total, stat.Current, int64(width))
 
-	if needTip {
-		progressWidth--
+	if s.rup > 0 {
+		rwidth := internal.Percentage(stat.Total, int64(s.rup), int64(width))
+		b = append(b, bytes.Repeat(s.format[rRefill], int(rwidth))...)
+		rest := cwidth - rwidth
+		b = append(b, bytes.Repeat(s.format[rFill], int(rest))...)
+	} else {
+		b = append(b, bytes.Repeat(s.format[rFill], int(cwidth))...)
 	}
 
-	if s.rup > 0 {
-		refillCount := internal.Percentage(stat.Total, int64(s.rup), int64(width))
-		rest := progressWidth - refillCount
-		str += runeRepeat(s.format[rRefill], int(refillCount)) + runeRepeat(s.format[rFill], int(rest))
-	} else {
-		str += runeRepeat(s.format[rFill], int(progressWidth))
+	if cwidth < int64(width) && cwidth > 0 {
+		_, size := utf8.DecodeLastRune(b)
+		b = append(b[:len(b)-size], s.format[rTip]...)
 	}
 
-	if needTip {
-		str += string(s.format[rTip])
-		progressWidth++
-	}
-
-	rest := int64(width) - progressWidth
-	str += runeRepeat(s.format[rEmpty], int(rest)) + string(s.format[rRight])
-	io.WriteString(w, str)
+	rest := int64(width) - cwidth
+	b = append(b, bytes.Repeat(s.format[rEmpty], int(rest))...)
+	w.Write(append(b, s.format[rRight]...))
 }
 
 func (s *barFiller) SetRefill(upto int) {
 	s.rup = upto
 }
-
-func runeRepeat(r rune, count int) string {
-	return strings.Repeat(string(r), count)
-}
diff --git a/bar_option.go b/bar_option.go
index 8449350..b85a99d 100644
--- a/bar_option.go
+++ b/bar_option.go
@@ -1,8 +1,6 @@
 package mpb
 
 import (
-	"unicode/utf8"
-
 	"github.com/vbauerster/mpb/v4/decor"
 )
 
@@ -116,10 +114,7 @@
 		return t, ok
 	}
 	cb := func(t interface{}) {
-		if !utf8.ValidString(style) {
-			return
-		}
-		copy(t.(*barFiller).format, []rune(style))
+		t.(*barFiller).setStyle(style)
 	}
 	return MakeFillerTypeSpecificBarOption(chk, cb)
 }
diff --git a/bar_test.go b/bar_test.go
index cf7e02f..a2a44b1 100644
--- a/bar_test.go
+++ b/bar_test.go
@@ -61,7 +61,7 @@
 
 	total := 100
 	till := 30
-	refillRune := DefaultBarStyle[len(DefaultBarStyle)-1]
+	refillRune, _ := utf8.DecodeLastRuneInString(DefaultBarStyle)
 
 	bar := p.AddBar(int64(total), TrimSpace())
 
diff --git a/draw_test.go b/draw_test.go
index 6867f81..456f5ce 100644
--- a/draw_test.go
+++ b/draw_test.go
@@ -3,6 +3,7 @@
 import (
 	"bytes"
 	"testing"
+	"unicode/utf8"
 )
 
 func TestDraw(t *testing.T) {
@@ -15,6 +16,142 @@
 		rup            int
 		want           string
 	}{
+		2: {
+			{
+				name:     "t,c,bw{60,20,80}",
+				total:    60,
+				current:  20,
+				barWidth: 80,
+				want:     "  ",
+			},
+			{
+				name:      "t,c,bw,trim{60,20,80,true}",
+				total:     60,
+				current:   20,
+				barWidth:  80,
+				trimSpace: true,
+				want:      "",
+			},
+		},
+		3: {
+			{
+				name:     "t,c,bw{60,20,80}",
+				total:    60,
+				current:  20,
+				barWidth: 80,
+				want:     "  ",
+			},
+			{
+				name:      "t,c,bw,trim{60,20,80,true}",
+				total:     60,
+				current:   20,
+				barWidth:  80,
+				trimSpace: true,
+				want:      "",
+			},
+		},
+		4: {
+			{
+				name:     "t,c,bw{60,20,80}",
+				total:    60,
+				current:  20,
+				barWidth: 80,
+				want:     "  ",
+			},
+			{
+				name:      "t,c,bw,trim{60,20,80,true}",
+				total:     60,
+				current:   20,
+				barWidth:  80,
+				trimSpace: true,
+				want:      "[]",
+			},
+		},
+		5: {
+			{
+				name:     "t,c,bw{60,20,80}",
+				total:    60,
+				current:  20,
+				barWidth: 80,
+				want:     "  ",
+			},
+			{
+				name:      "t,c,bw,trim{60,20,80,true}",
+				total:     60,
+				current:   20,
+				barWidth:  80,
+				trimSpace: true,
+				want:      "[>--]",
+			},
+		},
+		6: {
+			{
+				name:     "t,c,bw{60,20,80}",
+				total:    60,
+				current:  20,
+				barWidth: 80,
+				want:     " [] ",
+			},
+			{
+				name:      "t,c,bw,trim{60,20,80,true}",
+				total:     60,
+				current:   20,
+				barWidth:  80,
+				trimSpace: true,
+				want:      "[>---]",
+			},
+		},
+		7: {
+			{
+				name:     "t,c,bw{60,20,80}",
+				total:    60,
+				current:  20,
+				barWidth: 80,
+				want:     " [>--] ",
+			},
+			{
+				name:      "t,c,bw,trim{60,20,80,true}",
+				total:     60,
+				current:   20,
+				barWidth:  80,
+				trimSpace: true,
+				want:      "[=>---]",
+			},
+		},
+		8: {
+			{
+				name:     "t,c,bw{60,20,80}",
+				total:    60,
+				current:  20,
+				barWidth: 80,
+				want:     " [>---] ",
+			},
+			{
+				name:      "t,c,bw,trim{60,20,80,true}",
+				total:     60,
+				current:   20,
+				barWidth:  80,
+				trimSpace: true,
+				want:      "[=>----]",
+			},
+		},
+		80: {
+			{
+				name:     "t,c,bw{60,20,80}",
+				total:    60,
+				current:  20,
+				barWidth: 80,
+				want:     " [========================>---------------------------------------------------] ",
+			},
+			{
+				name:      "t,c,bw,trim{60,20,80,true}",
+				total:     60,
+				current:   20,
+				barWidth:  80,
+				trimSpace: true,
+				want:      "[=========================>----------------------------------------------------]",
+			},
+		},
 		100: {
 			{
 				name:     "t,c,bw{100,100,0}",
@@ -24,7 +161,7 @@
 				want:     " [------------------------------------------------------------------------------------------------] ",
 			},
 			{
-				name:      "t,c,bw{100,100,0}:trimSpace",
+				name:      "t,c,bw,trim{100,100,0,true}",
 				total:     100,
 				current:   0,
 				barWidth:  100,
@@ -39,7 +176,7 @@
 				want:     " [>-----------------------------------------------------------------------------------------------] ",
 			},
 			{
-				name:      "t,c,bw{100,1,100}:trimSpace",
+				name:      "t,c,bw,trim{100,1,100,true}",
 				total:     100,
 				current:   1,
 				barWidth:  100,
@@ -47,28 +184,53 @@
 				want:      "[>-------------------------------------------------------------------------------------------------]",
 			},
 			{
-				name:     "t,c,bw{100,40,100}",
+				name:     "t,c,bw{100,33,100}",
+				total:    100,
+				current:  33,
+				barWidth: 100,
+				want:     " [===============================>----------------------------------------------------------------] ",
+			},
+			{
+				name:      "t,c,bw,trim{100,33,100,true}",
+				total:     100,
+				current:   33,
+				barWidth:  100,
+				trimSpace: true,
+				want:      "[===============================>------------------------------------------------------------------]",
+			},
+			{
+				name:     "t,c,bw,rup{100,33,100,33}",
+				total:    100,
+				current:  33,
+				barWidth: 100,
+				rup:      33,
+				want:     " [+++++++++++++++++++++++++++++++>----------------------------------------------------------------] ",
+			},
+			{
+				name:      "t,c,bw,rup,trim{100,33,100,33,true}",
+				total:     100,
+				current:   33,
+				barWidth:  100,
+				rup:       33,
+				trimSpace: true,
+				want:      "[+++++++++++++++++++++++++++++++>------------------------------------------------------------------]",
+			},
+			{
+				name:     "t,c,bw,rup{100,40,100,32}",
 				total:    100,
 				current:  40,
 				barWidth: 100,
-				want:     " [=====================================>----------------------------------------------------------] ",
-			},
-			{
-				name:     "t,c,bw,rup{100,40,100,32}",
-				total:    100,
-				current:  40,
-				barWidth: 100,
-				rup:      32,
-				want:     " [+++++++++++++++++++++++++++++++======>----------------------------------------------------------] ",
-			},
-			{
-				name:      "t,c,bw,rup{100,40,100,32}:trimSpace",
+				rup:      33,
+				want:     " [++++++++++++++++++++++++++++++++=====>----------------------------------------------------------] ",
+			},
+			{
+				name:      "t,c,bw,rup,trim{100,40,100,32,true}",
 				total:     100,
 				current:   40,
 				barWidth:  100,
-				rup:       32,
-				trimSpace: true,
-				want:      "[+++++++++++++++++++++++++++++++=======>-----------------------------------------------------------]",
+				rup:       33,
+				trimSpace: true,
+				want:      "[++++++++++++++++++++++++++++++++======>-----------------------------------------------------------]",
 			},
 			{
 				name:     "t,c,bw{100,99,100}",
@@ -78,131 +240,27 @@
 				want:     " [==============================================================================================>-] ",
 			},
 			{
+				name:      "t,c,bw,trim{100,99,100,true}",
+				total:     100,
+				current:   99,
+				barWidth:  100,
+				trimSpace: true,
+				want:      "[================================================================================================>-]",
+			},
+			{
 				name:     "t,c,bw{100,100,100}",
 				total:    100,
 				current:  100,
 				barWidth: 100,
 				want:     " [================================================================================================] ",
 			},
-		},
-		2: {
-			{
-				name:     "t,c,bw{0,0,100}",
-				barWidth: 100,
-				want:     " [] ",
-			},
-			{
-				name:     "t,c,bw{60,20,80}",
-				total:    60,
-				current:  20,
-				barWidth: 80,
-				want:     " [] ",
-			},
-		},
-		4: {
-			{
-				name:     "t,c,bw{100,20,100}",
-				total:    100,
-				current:  20,
-				barWidth: 100,
-				want:     " [] ",
-			},
-			{
-				name:     "t,c,bw{100,98,100}",
-				total:    100,
-				current:  98,
-				barWidth: 100,
-				want:     " [] ",
-			},
-			{
-				name:     "t,c,bw{100,100,100}",
-				total:    100,
-				current:  100,
-				barWidth: 100,
-				want:     " [] ",
-			},
-		},
-		8: {
-			{
-				name:     "t,c,bw{100,20,100}",
-				total:    100,
-				current:  20,
-				barWidth: 100,
-				want:     " [>---] ",
-			},
-			{
-				name:     "t,c,bw{100,98,100}",
-				total:    100,
-				current:  98,
-				barWidth: 100,
-				want:     " [====] ",
-			},
-			{
-				name:     "t,c,bw{100,100,100}",
-				total:    100,
-				current:  100,
-				barWidth: 100,
-				want:     " [====] ",
-			},
-		},
-		20: {
-			{
-				name:     "t,c,bw{100,20,100}",
-				total:    100,
-				current:  20,
-				barWidth: 100,
-				want:     " [==>-------------] ",
-			},
-			{
-				name:     "t,c,bw{100,60,100}",
-				total:    100,
-				current:  60,
-				barWidth: 100,
-				want:     " [=========>------] ",
-			},
-			{
-				name:     "t,c,bw{100,98,100}",
-				total:    100,
-				current:  98,
-				barWidth: 100,
-				want:     " [================] ",
-			},
-			{
-				name:     "t,c,bw{100,100,100}",
-				total:    100,
-				current:  100,
-				barWidth: 100,
-				want:     " [================] ",
-			},
-		},
-		50: {
-			{
-				name:     "t,c,bw{100,20,100}",
-				total:    100,
-				current:  20,
-				barWidth: 100,
-				want:     " [========>-------------------------------------] ",
-			},
-			{
-				name:     "t,c,bw{100,60,100}",
-				total:    100,
-				current:  60,
-				barWidth: 100,
-				want:     " [===========================>------------------] ",
-			},
-			{
-				name:     "t,c,bw{100,98,100}",
-				total:    100,
-				current:  98,
-				barWidth: 100,
-				want:     " [============================================>-] ",
-			},
-			{
-				name:     "t,c,bw{100,100,100}",
-				total:    100,
-				current:  100,
-				barWidth: 100,
-				want:     " [==============================================] ",
+			{
+				name:      "t,c,bw,trim{100,100,100,true}",
+				total:     100,
+				current:   100,
+				barWidth:  100,
+				trimSpace: true,
+				want:      "[==================================================================================================]",
 			},
 		},
 	}
@@ -224,9 +282,14 @@
 			tmpBuf.ReadFrom(s.draw(termWidth))
 			by := tmpBuf.Bytes()
 			by = by[:len(by)-1]
+
+			if utf8.RuneCount(by) > termWidth {
+				t.Errorf("termWidth:%d %q barWidth:%d overflow termWidth\n", termWidth, tc.name, utf8.RuneCount(by))
+			}
+
 			got := string(by)
 			if got != tc.want {
-				t.Errorf("termWidth %d; %s: want: %q %d, got: %q %d\n", termWidth, tc.name, tc.want, len(tc.want), got, len(got))
+				t.Errorf("termWidth:%d %q want: %q %d, got: %q %d\n", termWidth, tc.name, tc.want, len(tc.want), got, len(got))
 			}
 		}
 	}
@@ -234,7 +297,7 @@
 
 func newTestState() *bState {
 	s := &bState{
-		filler: &barFiller{format: defaultBarStyle},
+		filler: newDefaultBarFiller(),
 		bufP:   new(bytes.Buffer),
 		bufB:   new(bytes.Buffer),
 		bufA:   new(bytes.Buffer),
diff --git a/progress.go b/progress.go
index 494441b..eee86ee 100644
--- a/progress.go
+++ b/progress.go
@@ -83,10 +83,7 @@
 
 // AddBar creates a new progress bar and adds to the container.
 func (p *Progress) AddBar(total int64, options ...BarOption) *Bar {
-	filler := &barFiller{
-		format: defaultBarStyle,
-	}
-	return p.Add(total, filler, options...)
+	return p.Add(total, newDefaultBarFiller(), options...)
 }
 
 // AddSpinner creates a new spinner bar and adds to the container.