diff --git a/core/fpdfapi/page/cpdf_psengine.cpp b/core/fpdfapi/page/cpdf_psengine.cpp
index b1e32f8..0de5652 100644
--- a/core/fpdfapi/page/cpdf_psengine.cpp
+++ b/core/fpdfapi/page/cpdf_psengine.cpp
@@ -170,7 +170,7 @@
   if (pFound != std::end(kPsOpNames) && pFound->name == word)
     m_Operators.push_back(pdfium::MakeUnique<CPDF_PSOP>(pFound->op));
   else
-    m_Operators.push_back(pdfium::MakeUnique<CPDF_PSOP>(FX_atof(word)));
+    m_Operators.push_back(pdfium::MakeUnique<CPDF_PSOP>(StringToFloat(word)));
 }
 
 CPDF_PSEngine::CPDF_PSEngine() = default;
diff --git a/core/fpdfdoc/cpdf_defaultappearance.cpp b/core/fpdfdoc/cpdf_defaultappearance.cpp
index 5db3ff7..c822b8e 100644
--- a/core/fpdfdoc/cpdf_defaultappearance.cpp
+++ b/core/fpdfdoc/cpdf_defaultappearance.cpp
@@ -63,7 +63,7 @@
   if (FindTagParamFromStart(&syntax, "Tf", 2)) {
     csFontNameTag = ByteString(syntax.GetWord());
     csFontNameTag.Delete(0, 1);
-    *fFontSize = FX_atof(syntax.GetWord());
+    *fFontSize = StringToFloat(syntax.GetWord());
   }
   return {PDF_NameDecode(csFontNameTag.AsStringView())};
 }
@@ -77,20 +77,20 @@
 
   CPDF_SimpleParser syntax(m_csDA.AsStringView().span());
   if (FindTagParamFromStart(&syntax, "g", 1)) {
-    fc[0] = FX_atof(syntax.GetWord());
+    fc[0] = StringToFloat(syntax.GetWord());
     return {CFX_Color::kGray};
   }
   if (FindTagParamFromStart(&syntax, "rg", 3)) {
-    fc[0] = FX_atof(syntax.GetWord());
-    fc[1] = FX_atof(syntax.GetWord());
-    fc[2] = FX_atof(syntax.GetWord());
+    fc[0] = StringToFloat(syntax.GetWord());
+    fc[1] = StringToFloat(syntax.GetWord());
+    fc[2] = StringToFloat(syntax.GetWord());
     return {CFX_Color::kRGB};
   }
   if (FindTagParamFromStart(&syntax, "k", 4)) {
-    fc[0] = FX_atof(syntax.GetWord());
-    fc[1] = FX_atof(syntax.GetWord());
-    fc[2] = FX_atof(syntax.GetWord());
-    fc[3] = FX_atof(syntax.GetWord());
+    fc[0] = StringToFloat(syntax.GetWord());
+    fc[1] = StringToFloat(syntax.GetWord());
+    fc[2] = StringToFloat(syntax.GetWord());
+    fc[3] = StringToFloat(syntax.GetWord());
     return {CFX_Color::kCMYK};
   }
 
diff --git a/core/fxcrt/bytestring.cpp b/core/fxcrt/bytestring.cpp
index fe09f7a..660f376 100644
--- a/core/fxcrt/bytestring.cpp
+++ b/core/fxcrt/bytestring.cpp
@@ -76,7 +76,7 @@
 // static
 ByteString ByteString::FormatFloat(float d) {
   char buf[32];
-  return ByteString(buf, FX_ftoa(d, buf));
+  return ByteString(buf, FloatToString(d, buf));
 }
 
 // static
diff --git a/core/fxcrt/cfx_widetextbuf.cpp b/core/fxcrt/cfx_widetextbuf.cpp
index 3d7da32..c2af175 100644
--- a/core/fxcrt/cfx_widetextbuf.cpp
+++ b/core/fxcrt/cfx_widetextbuf.cpp
@@ -50,7 +50,7 @@
 
 CFX_WideTextBuf& CFX_WideTextBuf::operator<<(double f) {
   char buf[32];
-  size_t len = FX_ftoa((float)f, buf);
+  size_t len = FloatToString((float)f, buf);
   ExpandBuf(len * sizeof(wchar_t));
   wchar_t* str = reinterpret_cast<wchar_t*>(m_pBuffer.get() + m_DataSize);
   for (size_t i = 0; i < len; i++) {
diff --git a/core/fxcrt/fx_number.cpp b/core/fxcrt/fx_number.cpp
index 68d5bd9..6c6e551 100644
--- a/core/fxcrt/fx_number.cpp
+++ b/core/fxcrt/fx_number.cpp
@@ -31,7 +31,7 @@
   if (strc.Contains('.')) {
     m_bInteger = false;
     m_bSigned = true;
-    m_FloatValue = FX_atof(strc);
+    m_FloatValue = StringToFloat(strc);
     return;
   }
 
diff --git a/core/fxcrt/fx_string.cpp b/core/fxcrt/fx_string.cpp
index 944f467..64bcd77 100644
--- a/core/fxcrt/fx_string.cpp
+++ b/core/fxcrt/fx_string.cpp
@@ -48,7 +48,7 @@
 
 }  // namespace
 
-float FX_atof(const ByteStringView& strc) {
+float StringToFloat(const ByteStringView& strc) {
   if (strc.IsEmpty())
     return 0.0;
 
@@ -87,11 +87,11 @@
   return bNegative ? -value : value;
 }
 
-float FX_atof(const WideStringView& wsStr) {
-  return FX_atof(FX_UTF8Encode(wsStr).c_str());
+float StringToFloat(const WideStringView& wsStr) {
+  return StringToFloat(FX_UTF8Encode(wsStr).c_str());
 }
 
-size_t FX_ftoa(float d, char* buf) {
+size_t FloatToString(float d, char* buf) {
   buf[0] = '0';
   buf[1] = '\0';
   if (d == 0.0f) {
diff --git a/core/fxcrt/fx_string.h b/core/fxcrt/fx_string.h
index 670aa4d..8d93150 100644
--- a/core/fxcrt/fx_string.h
+++ b/core/fxcrt/fx_string.h
@@ -19,8 +19,8 @@
 ByteString FX_UTF8Encode(const WideStringView& wsStr);
 WideString FX_UTF8Decode(const ByteStringView& bsStr);
 
-float FX_atof(const ByteStringView& str);
-float FX_atof(const WideStringView& wsStr);
-size_t FX_ftoa(float f, char* buf);
+float StringToFloat(const ByteStringView& str);
+float StringToFloat(const WideStringView& wsStr);
+size_t FloatToString(float f, char* buf);
 
 #endif  // CORE_FXCRT_FX_STRING_H_
diff --git a/fxjs/cjs_publicmethods.cpp b/fxjs/cjs_publicmethods.cpp
index f199996..a8209e2 100644
--- a/fxjs/cjs_publicmethods.cpp
+++ b/fxjs/cjs_publicmethods.cpp
@@ -917,11 +917,11 @@
     }
   }
 
-  int nDay = FX_atof(wsArray[2].AsStringView());
-  int nHour = FX_atof(wsArray[3].AsStringView());
-  int nMin = FX_atof(wsArray[4].AsStringView());
-  int nSec = FX_atof(wsArray[5].AsStringView());
-  int nYear = FX_atof(wsArray[7].AsStringView());
+  int nDay = StringToFloat(wsArray[2].AsStringView());
+  int nHour = StringToFloat(wsArray[3].AsStringView());
+  int nMin = StringToFloat(wsArray[4].AsStringView());
+  int nSec = StringToFloat(wsArray[5].AsStringView());
+  int nYear = StringToFloat(wsArray[7].AsStringView());
   double dRet = FX_MakeDate(FX_MakeDay(nYear, nMonth - 1, nDay),
                             FX_MakeTime(nHour, nMin, nSec, 0));
   if (std::isnan(dRet))
@@ -1297,7 +1297,7 @@
           WideString trimmed = pFormField->GetValue();
           trimmed.TrimRight();
           trimmed.TrimLeft();
-          dTemp = FX_atof(trimmed.AsStringView());
+          dTemp = StringToFloat(trimmed.AsStringView());
           break;
         }
         case FormFieldType::kPushButton:
@@ -1312,7 +1312,7 @@
             WideString trimmed = pFormCtrl->GetExportValue();
             trimmed.TrimRight();
             trimmed.TrimLeft();
-            dTemp = FX_atof(trimmed.AsStringView());
+            dTemp = StringToFloat(trimmed.AsStringView());
             break;
           }
           break;
@@ -1321,7 +1321,7 @@
             WideString trimmed = pFormField->GetValue();
             trimmed.TrimRight();
             trimmed.TrimLeft();
-            dTemp = FX_atof(trimmed.AsStringView());
+            dTemp = StringToFloat(trimmed.AsStringView());
           }
           break;
         default: