diff --git a/libs/openFrameworks/app/ofAppNoWindow.cpp b/libs/openFrameworks/app/ofAppNoWindow.cpp
index 3ca8f6e0b89..df462efb6dc 100644
--- a/libs/openFrameworks/app/ofAppNoWindow.cpp
+++ b/libs/openFrameworks/app/ofAppNoWindow.cpp
@@ -52,10 +52,10 @@ int kbhit()
 
 int getch()
 {
-    int r;
+    ssize_t r;
     unsigned char c;
     if ((r = read(0, &c, sizeof(c))) < 0) {
-        return r;
+        return (int)r;
     } else {
         return c;
     }
diff --git a/libs/openFrameworks/communication/ofArduino.cpp b/libs/openFrameworks/communication/ofArduino.cpp
index 59765988d28..9b6dc11e9a7 100644
--- a/libs/openFrameworks/communication/ofArduino.cpp
+++ b/libs/openFrameworks/communication/ofArduino.cpp
@@ -209,8 +209,8 @@ void ofArduino::update() {
 	if (bytesToRead > 0) {
 		bytesToProcess.resize(bytesToRead);
 		//its possible we dont get all the bytes
-		int bytesRead = _port.readBytes(&bytesToProcess[0], bytesToRead);
-		for (int i = 0; i < bytesRead; i++) {
+		long bytesRead = _port.readBytes(&bytesToProcess[0], bytesToRead);
+		for (long i = 0; i < bytesRead; i++) {
 			processData((char)(bytesToProcess[i]));
 		}
 	}
@@ -1369,7 +1369,7 @@ void  ofArduino::sendI2CWriteRequest(char slaveAddress, vector<char> bytes, int
 		if (reg >= 0) {
 			sendValueAsTwo7bitBytes(reg);
 		}
-		for (int i = 0, length = bytes.size(); i < length; i++) {
+		for (size_t i = 0, length = bytes.size(); i < length; i++) {
 			sendValueAsTwo7bitBytes(bytes[i]);
 		}
 
@@ -1799,7 +1799,7 @@ bool ofArduino::isPin(int pin) const
 
 //this returns the pin if its already not within the analog pin map
 //we need this to check between digital and analog pin mappings
-int ofArduino::convertAnalogPinToDigital(size_t pin) const
+int ofArduino::convertAnalogPinToDigital(int pin) const
 {
 	if (pin < analogPinMap.size()) {
 		if (analogPinMap.count(pin) > 0) {
@@ -1815,7 +1815,7 @@ int ofArduino::convertAnalogPinToDigital(size_t pin) const
 
 //this returns the pin if its already within the analog pin map
 //we need this to check between digital and analog pin mappings
-int ofArduino::convertDigitalPinToAnalog(size_t pin) const
+int ofArduino::convertDigitalPinToAnalog(int pin) const
 {
 	if (pin > analogPinMap.size()) {
 		for (auto aPin : analogPinMap)
diff --git a/libs/openFrameworks/communication/ofArduino.h b/libs/openFrameworks/communication/ofArduino.h
index 2feb5e81f11..f47ac699d05 100644
--- a/libs/openFrameworks/communication/ofArduino.h
+++ b/libs/openFrameworks/communication/ofArduino.h
@@ -813,8 +813,8 @@ class ofArduino {
 	bool isAnalogPin(int pin) const;
 	bool isPin(int pin) const;
 
-	int convertAnalogPinToDigital(size_t pin) const;
-	int convertDigitalPinToAnalog(size_t pin) const;
+	int convertAnalogPinToDigital(int pin) const;
+	int convertDigitalPinToAnalog(int pin) const;
 };
 
 typedef ofArduino ofStandardFirmata;
diff --git a/libs/openFrameworks/communication/ofSerial.cpp b/libs/openFrameworks/communication/ofSerial.cpp
index 5a76d972774..9e4fc096519 100644
--- a/libs/openFrameworks/communication/ofSerial.cpp
+++ b/libs/openFrameworks/communication/ofSerial.cpp
@@ -582,7 +582,7 @@ int ofSerial::readByte(){
 
 	#if defined( TARGET_OSX ) || defined( TARGET_LINUX )
 
-		int nRead = read(fd, &tmpByte, 1);
+		ssize_t nRead = read(fd, &tmpByte, 1);
 		if(nRead < 0){
 			if ( errno == EAGAIN ){
 				return OF_SERIAL_NO_DATA;
diff --git a/libs/openFrameworks/graphics/ofImage.cpp b/libs/openFrameworks/graphics/ofImage.cpp
index b6d85217730..af7450f8fa4 100644
--- a/libs/openFrameworks/graphics/ofImage.cpp
+++ b/libs/openFrameworks/graphics/ofImage.cpp
@@ -70,7 +70,7 @@ FIBITMAP* getBmpFromPixels(const ofPixels_<PixelType> &pix){
 	FIBITMAP* bmp = FreeImage_AllocateT(freeImageType, width, height, bpp);
 	unsigned char* bmpBits = FreeImage_GetBits(bmp);
 	if(bmpBits != nullptr) {
-		int srcStride = width * pix.getBytesPerPixel();
+		size_t srcStride = width * pix.getBytesPerPixel();
 		int dstStride = FreeImage_GetPitch(bmp);
 		unsigned char* src = (unsigned char*) pixels;
 		unsigned char* dst = bmpBits;
@@ -190,7 +190,7 @@ static bool loadImage(ofPixels_<PixelType> & pix, const std::filesystem::path& _
 	state.uri = &uri;
 
 	if(uriParseUriA(&state, uriStr.c_str())!=URI_SUCCESS){
-		const int bytesNeeded = 8 + 3 * strlen(uriStr.c_str()) + 1;
+		const size_t bytesNeeded = 8 + 3 * strlen(uriStr.c_str()) + 1;
 		std::vector<char> absUri(bytesNeeded);
 	#ifdef TARGET_WIN32
 		uriWindowsFilenameToUriStringA(uriStr.c_str(), absUri.data());
diff --git a/libs/openFrameworks/math/ofMath.cpp b/libs/openFrameworks/math/ofMath.cpp
index b8f00f321b9..45a02f317bf 100644
--- a/libs/openFrameworks/math/ofMath.cpp
+++ b/libs/openFrameworks/math/ofMath.cpp
@@ -12,9 +12,9 @@
 using namespace std;
 
 //--------------------------------------------------
-int ofNextPow2(int a){
+unsigned long ofNextPow2(unsigned long a){
 	// from nehe.gamedev.net lesson 43
-	int rval=1;
+	unsigned long rval=1;
 	while(rval<a) rval<<=1;
 	return rval;
 }
@@ -32,18 +32,18 @@ void ofSeedRandom() {
 		struct timeval tv;
 		gettimeofday(&tv, 0);
 		long int n = (tv.tv_sec ^ tv.tv_usec) ^ getpid();
-		srand(n);
+		srand((unsigned int)n);
 	#else
 		struct timeval tv;
 		gettimeofday(&tv, 0);
 		long int n = (tv.tv_sec ^ tv.tv_usec);
-		srand(n);
+		srand((unsigned int)n);
 	#endif
 }
 
 //--------------------------------------------------
-void ofSeedRandom(int val) {
-	srand((long) val);
+void ofSeedRandom(unsigned int val) {
+	srand((unsigned int)val);
 }
 
 //--------------------------------------------------
diff --git a/libs/openFrameworks/math/ofMath.h b/libs/openFrameworks/math/ofMath.h
index c07b40b63cb..997b0905c31 100644
--- a/libs/openFrameworks/math/ofMath.h
+++ b/libs/openFrameworks/math/ofMath.h
@@ -95,7 +95,7 @@ void ofSeedRandom();
 /// setup.  This can be useful for debugging and testing.
 ///
 /// \param val The value with which to seed the generator.
-void ofSeedRandom(int val);
+void ofSeedRandom(unsigned int val);
 
 /// \}
 
@@ -555,7 +555,7 @@ Type ofInterpolateHermite(const Type& y0, const Type& y1, const Type& y2, const
 ///
 /// \param a The starting point for finding the next power of 2.
 /// \returns value^2.
-int ofNextPow2(int a);
+unsigned long ofNextPow2(unsigned long a);
 
 /// \brief Returns the sign of a number.
 /// \returns int -1 if n is negative, 1 if n is positive, and 0 is n == 0;
diff --git a/libs/openFrameworks/sound/ofSoundBuffer.cpp b/libs/openFrameworks/sound/ofSoundBuffer.cpp
index 5bd3c9e295c..24a8da068cc 100644
--- a/libs/openFrameworks/sound/ofSoundBuffer.cpp
+++ b/libs/openFrameworks/sound/ofSoundBuffer.cpp
@@ -92,7 +92,7 @@ uint64_t ofSoundBuffer::getDurationNanos() const{
 	return uint64_t(getNumFrames()) * uint64_t(1000000000) / uint64_t(samplerate);
 }
 
-void ofSoundBuffer::setNumChannels(int channels){
+void ofSoundBuffer::setNumChannels(std::size_t channels){
 	this->channels = channels;
 	checkSizeAndChannelsConsistency("setNumChannels");
 }
@@ -243,15 +243,11 @@ void ofSoundBuffer::copyTo(float * outBuffer, std::size_t nFrames, std::size_t o
 	}
 
 	// do we have anything left?
-	int framesRemaining = nFrames - (int)nFramesToCopy;
-	if (framesRemaining > 0){
-		if(!loop || size() == 0){
-			// fill with 0s
-			for(std::size_t i = 0; i < framesRemaining * outChannels; i++){
-				outBuffer[i] = 0;
-			}
-		}else{
-			// loop
+	if(nFramesToCopy < nFrames) {
+		std::size_t framesRemaining = nFrames - nFramesToCopy;
+		if(!loop || size() == 0) {
+			std::fill_n(outBuffer, framesRemaining * outChannels, 0.0f);
+		} else {
 			copyTo(outBuffer, framesRemaining, outChannels, 0, loop);
 		}
 	}
@@ -294,8 +290,8 @@ void ofSoundBuffer::addTo(float * outBuffer, std::size_t nFrames, std::size_t ou
 	}
 
 	// do we have anything left?
-	int framesRemaining = nFrames - (int)nFramesToCopy;
-	if (framesRemaining > 0 && loop){
+	if (nFrames > nFramesToCopy && loop){
+		std::size_t framesRemaining = nFrames - nFramesToCopy;
 		// loop
 		addTo(outBuffer, framesRemaining, outChannels, 0, loop);
 	}
diff --git a/libs/openFrameworks/sound/ofSoundBuffer.h b/libs/openFrameworks/sound/ofSoundBuffer.h
index 22a74e2c515..e305492907f 100644
--- a/libs/openFrameworks/sound/ofSoundBuffer.h
+++ b/libs/openFrameworks/sound/ofSoundBuffer.h
@@ -102,7 +102,7 @@ class ofSoundBuffer {
 	/// the number of channels per frame
 	std::size_t getNumChannels() const { return channels; }
 	/// set the number of channels. does not change the underlying data, ie causes getNumFrames() to return a different result.
-	void setNumChannels(int channels);
+	void setNumChannels(std::size_t channels);
 	/// the number of frames, ie the number of sets of (getNumChannels()) samples
 	std::size_t getNumFrames() const { return size()/getNumChannels(); }
 	
diff --git a/libs/openFrameworks/video/ofAVFoundationGrabber.h b/libs/openFrameworks/video/ofAVFoundationGrabber.h
index 1ace79c78a7..8f061655314 100644
--- a/libs/openFrameworks/video/ofAVFoundationGrabber.h
+++ b/libs/openFrameworks/video/ofAVFoundationGrabber.h
@@ -33,7 +33,7 @@ class ofAVFoundationGrabber;
 	int height;
 
 	BOOL bInitCalled;
-	int deviceID;
+	NSUInteger deviceID;
 
 	AVCaptureDeviceInput		*captureInput;
 	AVCaptureVideoDataOutput    *captureOutput;