diff --git a/code/espurna/dht.ino b/code/espurna/dht.ino
index 5dd5b199..8655b20c 100644
--- a/code/espurna/dht.ino
+++ b/code/espurna/dht.ino
@@ -34,7 +34,7 @@ void dhtSetup() {
 
     #if WEB_SUPPORT
         apiRegister(DHT_TEMPERATURE_TOPIC, DHT_TEMPERATURE_TOPIC, [](char * buffer, size_t len) {
-            dtostrf(_dhtTemperature, len-1, 1, buffer);
+            dtostrf(_dhtTemperature, 1-len, 1, buffer);
         });
         apiRegister(DHT_HUMIDITY_TOPIC, DHT_HUMIDITY_TOPIC, [](char * buffer, size_t len) {
             snprintf_P(buffer, len, PSTR("%d"), _dhtHumidity);
@@ -68,7 +68,7 @@ void dhtLoop() {
 
             char temperature[6];
             char humidity[6];
-            dtostrf(t, 4, 1, temperature);
+            dtostrf(t, 1-sizeof(temperature), 1, temperature);
             itoa((unsigned int) h, humidity, 10);
 
             DEBUG_MSG_P(PSTR("[DHT] Temperature: %s%s\n"), temperature, (tmpUnits == TMP_CELSIUS) ? "ºC" : "ºF");
diff --git a/code/espurna/ds18b20.ino b/code/espurna/ds18b20.ino
index a7a7ff74..ebe98160 100644
--- a/code/espurna/ds18b20.ino
+++ b/code/espurna/ds18b20.ino
@@ -40,7 +40,7 @@ void dsSetup() {
 
     #if WEB_SUPPORT
         apiRegister(DS18B20_TEMPERATURE_TOPIC, DS18B20_TEMPERATURE_TOPIC, [](char * buffer, size_t len) {
-            dtostrf(_dsTemperature, len-1, 1, buffer);
+            dtostrf(_dsTemperature, 1-len, 1, buffer);
         });
     #endif
 
@@ -89,7 +89,7 @@ void dsLoop() {
             else
             	_dsIsConnected = true;
 
-            dtostrf(t, 5, 1, _dsTemperatureStr);
+            dtostrf(t, 1-sizeof(_dsTemperatureStr), 1, _dsTemperatureStr);
 
             DEBUG_MSG_P(PSTR("[DS18B20] Temperature: %s%s\n"),
                 getDSTemperatureStr(),
diff --git a/code/espurna/emon.ino b/code/espurna/emon.ino
index 160e698b..c6507f7a 100644
--- a/code/espurna/emon.ino
+++ b/code/espurna/emon.ino
@@ -116,7 +116,7 @@ void powerMonitorSetup() {
 
         apiRegister(EMON_CURRENT_TOPIC, EMON_CURRENT_TOPIC, [](char * buffer, size_t len) {
             if (_emonReady) {
-                dtostrf(_emonCurrent, len-1, 3, buffer);
+                dtostrf(_emonCurrent, 1-len, 3, buffer);
             } else {
                 buffer = NULL;
             }
diff --git a/code/espurna/hlw8012.ino b/code/espurna/hlw8012.ino
index 928311bf..b8a2b8e3 100644
--- a/code/espurna/hlw8012.ino
+++ b/code/espurna/hlw8012.ino
@@ -170,7 +170,7 @@ void hlw8012Setup() {
         });
         apiRegister(HLW8012_CURRENT_TOPIC, HLW8012_CURRENT_TOPIC, [](char * buffer, size_t len) {
             if (_hlwReady) {
-                dtostrf(_hlwCurrent, len-1, 3, buffer);
+                dtostrf(_hlwCurrent, 1-len, 3, buffer);
             } else {
                 buffer = NULL;
             }
diff --git a/code/espurna/v9261f.ino b/code/espurna/v9261f.ino
index 5bc7334f..c244ebfc 100644
--- a/code/espurna/v9261f.ino
+++ b/code/espurna/v9261f.ino
@@ -193,7 +193,7 @@ void v9261fSetup() {
             snprintf_P(buffer, len, PSTR("%d"), _v9261f_power);
         });
         apiRegister(HLW8012_CURRENT_TOPIC, HLW8012_CURRENT_TOPIC, [](char * buffer, size_t len) {
-            dtostrf(_v9261f_current, len-1, 3, buffer);
+            dtostrf(_v9261f_current, 1-len, 3, buffer);
         });
         apiRegister(HLW8012_VOLTAGE_TOPIC, HLW8012_VOLTAGE_TOPIC, [](char * buffer, size_t len) {
             snprintf_P(buffer, len, PSTR("%d"), _v9261f_voltage);
@@ -232,11 +232,11 @@ void v9261fLoop() {
             JsonObject& root = jsonBuffer.createObject();
 
             char buf_current[10];
-            dtostrf(getCurrent(), 6, 3, buf_current);
+            dtostrf(getCurrent(), 1-sizeof(buf_current), 3, buf_current);
 
             root["powVisible"] = 1;
             root["powActivePower"] = getActivePower();
-            root["powCurrent"] = String(ltrim(buf_current));
+            root["powCurrent"] = String(buf_current);
             root["powVoltage"] = getVoltage();
             root["powApparentPower"] = getApparentPower();
             root["powReactivePower"] = getReactivePower();
@@ -262,11 +262,11 @@ void v9261fLoop() {
         unsigned int voltage = sum_voltage / count;
         double current = sum_current / count;
         char buf_current[10];
-        dtostrf(current, 6, 3, buf_current);
+        dtostrf(current, 1-sizeof(buf_current), 3, buf_current);
         unsigned int apparent = sqrt(power * power + reactive * reactive);
         double energy_delta = (double) power * V9261F_REPORT_INTERVAL / 1000.0 / 3600.0;
         char buf_energy[10];
-        dtostrf(energy_delta, 6, 3, buf_energy);
+        dtostrf(energy_delta, 1-sizeof(buf_energy), 3, buf_energy);
         unsigned int factor = 100 * ((double) power / apparent);
 
         // Report values to MQTT broker
diff --git a/code/espurna/web.ino b/code/espurna/web.ino
index eed32a45..1b2cf4ed 100644
--- a/code/espurna/web.ino
+++ b/code/espurna/web.ino
@@ -809,7 +809,6 @@ ArRequestHandlerFunction _bindAPI(unsigned int apiID) {
         // Get response from callback
         char value[API_BUFFER_SIZE];
         (api.getFn)(value, API_BUFFER_SIZE);
-        char *p = ltrim(value);
 
         // The response will be a 404 NOT FOUND if the resource is not available
         if (!value) {
@@ -817,15 +816,15 @@ ArRequestHandlerFunction _bindAPI(unsigned int apiID) {
             request->send(404);
             return;
         }
-        DEBUG_MSG_P(PSTR("[API] Sending response '%s'\n"), p);
+        DEBUG_MSG_P(PSTR("[API] Sending response '%s'\n"), value);
 
         // Format response according to the Accept header
         if (_asJson(request)) {
             char buffer[64];
-            snprintf_P(buffer, sizeof(buffer), PSTR("{ \"%s\": %s }"), api.key, p);
+            snprintf_P(buffer, sizeof(buffer), PSTR("{ \"%s\": %s }"), api.key, value);
             request->send(200, "application/json", buffer);
         } else {
-            request->send(200, "text/plain", p);
+            request->send(200, "text/plain", value);
         }
 
     };