diff --git a/pkg/fixedpoint/convert.go b/pkg/fixedpoint/convert.go
index 6d8a54158..1d025abf1 100644
--- a/pkg/fixedpoint/convert.go
+++ b/pkg/fixedpoint/convert.go
@@ -347,6 +347,7 @@ func NewFromString(input string) (Value, error) {
 	decimalCount := 0
 	// if is decimal, we don't need this
 	hasScientificNotion := false
+	hasIChar := false
 	scIndex := -1
 	for i, c := range input {
 		if hasDecimal {
@@ -365,6 +366,10 @@ func NewFromString(input string) (Value, error) {
 			scIndex = i
 			break
 		}
+		if c == 'i' || c == 'I' {
+			hasIChar = true
+			break
+		}
 	}
 	if hasDecimal {
 		after := input[dotIndex+1:]
@@ -395,6 +400,16 @@ func NewFromString(input string) (Value, error) {
 			return 0, err
 		}
 		return Value(int64(math.Trunc(v))), nil
+	} else if hasIChar {
+		if floatV, err := strconv.ParseFloat(input, 64); nil != err {
+			return 0, err
+		} else if math.IsInf(floatV, 1) {
+			return PosInf, nil
+		} else if math.IsInf(floatV, -1) {
+			return NegInf, nil
+		} else {
+			return 0, fmt.Errorf("fixedpoint.Value parse error, invalid input string %s", input)
+		}
 	} else {
 		v, err := strconv.ParseInt(input, 10, 64)
 		if err != nil {
diff --git a/pkg/fixedpoint/dec.go b/pkg/fixedpoint/dec.go
index 1b279bdfe..2b5f3743b 100644
--- a/pkg/fixedpoint/dec.go
+++ b/pkg/fixedpoint/dec.go
@@ -500,7 +500,7 @@ func NewFromString(s string) (Value, error) {
 	}
 	r := &reader{s, 0}
 	sign := r.getSign()
-	if r.matchStr("inf") {
+	if r.matchStrIgnoreCase("inf") {
 		return Inf(sign), nil
 	}
 	coef, exp := r.getCoef()
@@ -550,7 +550,7 @@ func NewFromBytes(s []byte) (Value, error) {
 	}
 	r := &readerBytes{s, 0}
 	sign := r.getSign()
-	if r.matchStr("inf") {
+	if r.matchStrIgnoreCase("inf") {
 		return Inf(sign), nil
 	}
 	coef, exp := r.getCoef()
@@ -631,13 +631,18 @@ func (r *readerBytes) matchDigit() bool {
 	return false
 }
 
-func (r *readerBytes) matchStr(pre string) bool {
-	for i, c := range r.s[r.i:] {
+func (r *readerBytes) matchStrIgnoreCase(pre string) bool {
+	pre = strings.ToLower(pre)
+	boundary := r.i + len(pre)
+	if boundary > len(r.s) {
+		return false
+	}
+	for i, c := range bytes.ToLower(r.s[r.i:boundary]) {
 		if pre[i] != c {
 			return false
 		}
 	}
-	r.i += len(pre)
+	r.i = boundary
 	return true
 }
 
@@ -745,9 +750,15 @@ func (r *reader) matchDigit() bool {
 	return false
 }
 
-func (r *reader) matchStr(pre string) bool {
-	if strings.HasPrefix(r.s[r.i:], pre) {
-		r.i += len(pre)
+func (r *reader) matchStrIgnoreCase(pre string) bool {
+	boundary := r.i + len(pre)
+	if boundary > len(r.s) {
+		return false
+	}
+	data := strings.ToLower(r.s[r.i:boundary])
+	pre = strings.ToLower(pre)
+	if data == pre {
+		r.i = boundary
 		return true
 	}
 	return false
diff --git a/pkg/fixedpoint/dec_test.go b/pkg/fixedpoint/dec_test.go
index 269904c1b..8c72582f6 100644
--- a/pkg/fixedpoint/dec_test.go
+++ b/pkg/fixedpoint/dec_test.go
@@ -138,6 +138,15 @@ func TestFromString(t *testing.T) {
 	assert.Equal(t, Zero, f)
 	f = MustNewFromString("")
 	assert.Equal(t, Zero, f)
+
+	for _, s := range []string{"inf", "Inf", "INF", "iNF"} {
+		f = MustNewFromString(s)
+		assert.Equal(t, PosInf, f)
+		f = MustNewFromString("+" + s)
+		assert.Equal(t, PosInf, f)
+		f = MustNewFromString("-" + s)
+		assert.Equal(t, NegInf, f)
+	}
 }
 
 func TestJson(t *testing.T) {
@@ -177,6 +186,10 @@ func TestJson(t *testing.T) {
 	_ = json.Unmarshal([]byte("0.000062"), &q)
 	assert.Equal(t, "0.00006194", q.Sub(p).String())
 
+	assert.NoError(t, json.Unmarshal([]byte(`"inf"`), &p))
+	assert.NoError(t, json.Unmarshal([]byte(`"+Inf"`), &q))
+	assert.Equal(t, PosInf, p)
+	assert.Equal(t, p, q)
 }
 
 func TestYaml(t *testing.T) {
@@ -216,6 +229,10 @@ func TestYaml(t *testing.T) {
 	_ = yaml.Unmarshal([]byte("0.000062"), &q)
 	assert.Equal(t, "0.00006194", q.Sub(p).String())
 
+	assert.NoError(t, json.Unmarshal([]byte(`"inf"`), &p))
+	assert.NoError(t, json.Unmarshal([]byte(`"+Inf"`), &q))
+	assert.Equal(t, PosInf, p)
+	assert.Equal(t, p, q)
 }
 
 func TestNumFractionalDigits(t *testing.T) {