diff --git a/libs/banglejs/jswrap_bangle.c b/libs/banglejs/jswrap_bangle.c
index c3c5792e6..d651dc9a8 100644
--- a/libs/banglejs/jswrap_bangle.c
+++ b/libs/banglejs/jswrap_bangle.c
@@ -4016,7 +4016,7 @@ NO_INLINE void jswrap_banglejs_init() {
     bool drawInfo = false;
     JsVar *img = jsfReadFile(jsfNameFromString(".splash"),0,0);
     int w,h;
-    if (!jsvIsString(img) || !jsvGetStringLength(img)) {
+    if (!jsvIsString(img) || jsvIsEmptyString(img)) {
       jsvUnLock(img);
       drawInfo = true;
       img = jswrap_banglejs_getLogo();
diff --git a/libs/graphics/jswrap_graphics.c b/libs/graphics/jswrap_graphics.c
index a186a57aa..dde4defe6 100644
--- a/libs/graphics/jswrap_graphics.c
+++ b/libs/graphics/jswrap_graphics.c
@@ -2012,7 +2012,7 @@ JsVar *jswrap_graphics_setFont(JsVar *parent, JsVar *fontId, int size) {
   unsigned short sz = 0xFFFF; // the actual data mask
   if (isVector) {
     sz = (unsigned short)size;
-  } else if (jsvIsUndefined(name) || jsvGetStringLength(name)==0 || jsvIsStringEqual(name, "4x6"))
+  } else if (jsvIsUndefined(name) || jsvIsEmptyString(name) || jsvIsStringEqual(name, "4x6"))
     sz = (unsigned short)(size + JSGRAPHICS_FONTSIZE_4X6);
 #ifdef USE_FONT_6X8
   if (jsvIsStringEqual(name, "6x8"))
@@ -2497,7 +2497,7 @@ JsVar *jswrap_graphics_wrapString(JsVar *parent, JsVar *str, int maxWidth) {
         lineWidth += wordWidth;
       } else { // doesn't fit on one line - put word on new line
         lineWidth = wordWidth;
-        if (jsvGetStringLength(currentLine) || wasNewLine)
+        if (!jsvIsEmptyString(currentLine) || wasNewLine)
           jsvArrayPush(lines, currentLine);
         jsvUnLock(currentLine);
         currentLine = 0;
@@ -2587,7 +2587,7 @@ JsVar *jswrap_graphics_wrapString(JsVar *parent, JsVar *str, int maxWidth) {
   }
   jsvStringIteratorFree(&it);
   // deal with final line
-  if (jsvGetStringLength(currentLine)) {
+  if (!jsvIsEmptyString(currentLine)) {
     jsvArrayPush(lines, currentLine);
   }
   jsvUnLock2(str,currentLine);
@@ -3903,7 +3903,7 @@ JsVar *jswrap_graphics_drawImages(JsVar *parent, JsVar *layersVar, JsVar *option
         // compose operation
         JsVar *opVar = jsvObjectGetChildIfExists(layer,"compose");
         layers[i].compose = GFXDILC_REPLACE;
-        if (!opVar || !jsvGetStringLength(opVar)) layers[i].compose = GFXDILC_REPLACE;
+        if (!opVar || jsvIsEmptyString(opVar)) layers[i].compose = GFXDILC_REPLACE;
         else if (jsvIsStringEqual(opVar,"add")) layers[i].compose = GFXDILC_ADD;
         else if (jsvIsStringEqual(opVar,"or")) layers[i].compose = GFXDILC_OR;
         else if (jsvIsStringEqual(opVar,"xor")) layers[i].compose = GFXDILC_XOR;
diff --git a/libs/network/esp8266/jswrap_esp8266_network.c b/libs/network/esp8266/jswrap_esp8266_network.c
index 4b1e47493..95b749cbc 100644
--- a/libs/network/esp8266/jswrap_esp8266_network.c
+++ b/libs/network/esp8266/jswrap_esp8266_network.c
@@ -568,7 +568,7 @@ void jswrap_wifi_startAP(
     JsVar *jsPassword = jsvObjectGetChildIfExists(jsOptions, "password");
     if (jsPassword != NULL) {
       // handle password:null
-      if (jsvGetStringLength(jsPassword) != 0) {
+      if (!jsvIsEmptyString(jsPassword)) {
         if (!jsvIsString(jsPassword) || jsvGetStringLength(jsPassword) < 8) {
           jsExceptionHere(JSET_ERROR, "Password must be string of at least 8 characters");
           jsvUnLock(jsPassword);
diff --git a/libs/network/jswrap_net.c b/libs/network/jswrap_net.c
index 783507ad8..b7505cc24 100644
--- a/libs/network/jswrap_net.c
+++ b/libs/network/jswrap_net.c
@@ -143,11 +143,11 @@ JsVar *jswrap_url_parse(JsVar *url, bool parseQuery) {
   JsVar *v;
 
   v = jsvNewWritableStringFromStringVar(url, (size_t)pathStart, JSVAPPENDSTRINGVAR_MAXLENGTH);
-  if (jsvGetStringLength(v)==0) jsvAppendString(v, "/");
+  if (jsvIsEmptyString(v)) jsvAppendString(v, "/");
   jsvObjectSetChildAndUnLock(obj, "path", v);
 
   v = jsvNewWritableStringFromStringVar(url, (size_t)pathStart, (size_t)((searchStart>=0)?(searchStart-pathStart):JSVAPPENDSTRINGVAR_MAXLENGTH));
-  if (jsvGetStringLength(v)==0) jsvAppendString(v, "/");
+  if (jsvIsEmptyString(v)) jsvAppendString(v, "/");
   jsvObjectSetChildAndUnLock(obj, "pathname", v);
 
   jsvObjectSetChildAndUnLock(obj, "search", (searchStart>=0)?jsvNewFromStringVar(url, (size_t)searchStart, JSVAPPENDSTRINGVAR_MAXLENGTH):jsvNewNull());
@@ -167,7 +167,7 @@ JsVar *jswrap_url_parse(JsVar *url, bool parseQuery) {
     while (jsvStringIteratorHasChar(&it)) {
       char ch = jsvStringIteratorGetCharAndNext(&it);
       if (ch=='&') {
-        if (jsvGetStringLength(key)>0 || jsvGetStringLength(val)>0) {
+        if (!jsvIsEmptyString(key) || !jsvIsEmptyString(val)) {
           key = jsvAsArrayIndexAndUnLock(key); // make sure "0" gets made into 0
           key = jsvMakeIntoVariableName(key, val);
           jsvAddName(query, key);
@@ -194,7 +194,7 @@ JsVar *jswrap_url_parse(JsVar *url, bool parseQuery) {
     jsvStringIteratorFree(&it);
     jsvUnLock(queryStr);
 
-    if (jsvGetStringLength(key)>0 || jsvGetStringLength(val)>0) {
+    if (!jsvIsEmptyString(key) || !jsvIsEmptyString(val)) {
       key = jsvAsArrayIndexAndUnLock(key); // make sure "0" gets made into 0
       key = jsvMakeIntoVariableName(key, val);
       jsvAddName(query, key);
diff --git a/libs/network/socketserver.c b/libs/network/socketserver.c
index e9cba4331..213de41da 100644
--- a/libs/network/socketserver.c
+++ b/libs/network/socketserver.c
@@ -696,7 +696,7 @@ bool socketClientConnectionsIdle(JsNetwork *net) {
             jsvObjectSetChildAndUnLock(connection, HTTP_NAME_CONNECTED, jsvNewFromBool(true));
             alreadyConnected = true;
             // if we do not have any data to send, issue a drain event
-            if (!sendData || (int)jsvGetStringLength(sendData) == 0)
+            if (!sendData || jsvIsEmptyString(sendData))
               jsiQueueObjectCallbacks(connection, HTTP_NAME_ON_DRAIN, &connection, 1);
           }
           // got data add it to our receive buffer
@@ -721,7 +721,7 @@ bool socketClientConnectionsIdle(JsNetwork *net) {
       if (!receiveData || jsvIsEmptyString(receiveData)) {
         // If we had data to send but the socket closed, this is an error
         JsVar *sendData = jsvObjectGetChildIfExists(connection,HTTP_NAME_SEND_DATA);
-        if (sendData && jsvGetStringLength(sendData) > 0 && error == SOCKET_ERR_CLOSED)
+        if (sendData && !jsvIsEmptyString(sendData) && error == SOCKET_ERR_CLOSED)
           error = SOCKET_ERR_UNSENT_DATA;
         jsvUnLock(sendData);
 
diff --git a/libs/pixljs/jswrap_pixljs.c b/libs/pixljs/jswrap_pixljs.c
index 2a630540c..a16e378e6 100644
--- a/libs/pixljs/jswrap_pixljs.c
+++ b/libs/pixljs/jswrap_pixljs.c
@@ -426,7 +426,7 @@ void jswrap_pixljs_init() {
         (jshPinGetValue(BTN4_PININDEX) == BTN4_ONSTATE)))
     splashScreen = jsfReadFile(jsfNameFromString(".splash"),0,0);
   if (jsvIsString(splashScreen)) {
-    if (jsvGetStringLength(splashScreen)) {
+    if (!jsvIsEmptyString(splashScreen)) {
       graphicsSetVar(&gfx);
       jsvUnLock(jswrap_graphics_drawImage(graphics, splashScreen,0,0,0));
       graphicsGetFromVar(&gfx, graphics);
diff --git a/src/jsinteractive.c b/src/jsinteractive.c
index ca174d742..fa1de70b4 100644
--- a/src/jsinteractive.c
+++ b/src/jsinteractive.c
@@ -1860,7 +1860,7 @@ static void jsiHandleConsoleChar(char ch) {
       execInfo.execute &= ~EXEC_CTRL_C_MASK; // if we got Ctrl-C, ignore it
 
   if (inputState == IPS_PACKET_TRANSFER_BYTE0) {
-    if (jsvGetStringLength(inputLine)==0)
+    if (jsvIsEmptyString(inputLine))
       jsiStatus &= ~JSIS_ECHO_OFF_FOR_LINE; // turn on echo (because it'd have been turned off by DLE on an empty line)
     inputPacketLength = ((uint8_t)ch) << 8;
     inputState = IPS_PACKET_TRANSFER_BYTE1;
@@ -1882,13 +1882,13 @@ static void jsiHandleConsoleChar(char ch) {
   } else if (ch == 3) { // Ctrl-c
     // Ctrl-C (char code 3) gets handled in an IRQ but we just ignore it here
   } else if (ch == 5) { // Ctrl-e
-    if (jsvGetStringLength(inputLine)==0)
+    if (jsvIsEmptyString(inputLine))
       jsiConsolePrintf("Espruino %s %s\n",JS_VERSION,PC_BOARD_ID); // 5=ENQ - if sent on empty line and Espruino new enough, we transmit what we are
   } else if (ch==16) {
     /* DLE - Data Link Escape
     Espruino uses DLE on the start of a line to signal that just the line in
     question should be executed without echo */
-    if (jsvGetStringLength(inputLine)==0)
+    if (jsvIsEmptyString(inputLine))
       jsiStatus |= JSIS_ECHO_OFF_FOR_LINE;
     inputState = IPS_HAD_DLE;
   } else if (ch == 27) {
diff --git a/src/jsvar.c b/src/jsvar.c
index c34cbfff7..9acf52e99 100644
--- a/src/jsvar.c
+++ b/src/jsvar.c
@@ -2245,7 +2245,7 @@ void jsvSetInteger(JsVar *v, JsVarInt value) {
  */
 bool jsvGetBool(const JsVar *v) {
   if (jsvIsString(v))
-    return jsvGetStringLength((JsVar*)v)!=0;
+    return !jsvIsEmptyString((JsVar*)v);
 #ifndef ESPR_EMBED
   if (jsvIsPin(v))
     return jshIsPinValid(jshGetPinFromVar((JsVar*)v));
diff --git a/src/jswrap_modules.c b/src/jswrap_modules.c
index 26b68b3b4..127ad2366 100644
--- a/src/jswrap_modules.c
+++ b/src/jswrap_modules.c
@@ -133,7 +133,7 @@ JsVar *jswrap_require(JsVar *moduleName) {
         jsvUnLock2(fileContents, exception);
         fileContents = 0;
       }
-      if (fileContents && jsvGetStringLength(fileContents)>0)
+      if (fileContents && !jsvIsEmptyString(fileContents))
         moduleExport = jspEvaluateModule(fileContents);
       jsvUnLock(fileContents);
     }
diff --git a/targets/esp8266/jswrap_esp8266.c b/targets/esp8266/jswrap_esp8266.c
index 588e3a9f6..ed346b1d3 100644
--- a/targets/esp8266/jswrap_esp8266.c
+++ b/targets/esp8266/jswrap_esp8266.c
@@ -149,7 +149,7 @@ Prints the contents of the debug log to the console.
  */
 void jswrap_ESP8266_printLog() {
   JsVar *line = esp8266_logGetLine();
-  while (jsvGetStringLength(line) > 0) {
+  while (!jsvIsEmptyString(line)) {
     jsiConsolePrintStringVar(line);
     jsvUnLock(line);
     line = esp8266_logGetLine();