diff --git a/src/bmffimage.cpp b/src/bmffimage.cpp
index 28c8a0c8..8628951f 100644
--- a/src/bmffimage.cpp
+++ b/src/bmffimage.cpp
@@ -299,7 +299,7 @@ namespace Exiv2
                     bLF = false;
                 }
                 io_->seek(skip, BasicIo::cur);
-                while (io_->tell() < (address + box.length)) {
+                while (io_->tell() < static_cast<long>((address + box.length))) {
                     io_->seek(boxHandler(out,option,depth + 1), BasicIo::beg);
                 }
                 // post-process meta box to recover Exif and XMP
@@ -417,7 +417,7 @@ namespace Exiv2
                     bLF = false;
                 }
                 if (name == "cano") {
-                    while (io_->tell() < (address + box.length)) {
+                    while (io_->tell() < static_cast<long>(address + box.length)) {
                         io_->seek(boxHandler(out,option,depth + 1), BasicIo::beg);
                     }
                 } else if ( name == "xmp" ) {
diff --git a/src/http.cpp b/src/http.cpp
index 96e3f942..d05babec 100644
--- a/src/http.cpp
+++ b/src/http.cpp
@@ -252,7 +252,7 @@ int Exiv2::http(Exiv2::Dictionary& request,Exiv2::Dictionary& response,std::stri
 
     ////////////////////////////////////
     // open the socket
-    int     sockfd = socket(AF_INET , SOCK_STREAM,IPPROTO_TCP) ;
+    int sockfd = static_cast<int>(socket(AF_INET , SOCK_STREAM,IPPROTO_TCP));
     if (sockfd < 0)
         return error(errors, "unable to create socket\n", NULL, NULL, 0);
 
diff --git a/src/jpgimage.cpp b/src/jpgimage.cpp
index cbc96f0a..30841cd2 100644
--- a/src/jpgimage.cpp
+++ b/src/jpgimage.cpp
@@ -126,7 +126,7 @@ namespace Exiv2 {
         const byte* pEnd = pPsData + sizePsData;
         int ret = 0;
         while (pCur < pEnd
-               && 0 == (ret = Photoshop::locateIptcIrb(pCur, pEnd - pCur,
+               && 0 == (ret = Photoshop::locateIptcIrb(pCur, static_cast<long>(pEnd - pCur),
                                                        &record, &sizeHdr, &sizeIptc))) {
             pCur = record + sizeHdr + sizeIptc + (sizeIptc & 1);
         }
@@ -539,7 +539,7 @@ namespace Exiv2 {
             const byte* pCur = &psBlob[0];
             const byte* pEnd = pCur + psBlob.size();
             while (   pCur < pEnd
-                   && 0 == Photoshop::locateIptcIrb(pCur, pEnd - pCur,
+                   && 0 == Photoshop::locateIptcIrb(pCur, static_cast<long>(pEnd - pCur),
                                                     &record, &sizeHdr, &sizeIptc)) {
 #ifdef EXIV2_DEBUG_MESSAGES
                 std::cerr << "Found IPTC IRB, size = " << sizeIptc << "\n";
@@ -1200,11 +1200,11 @@ namespace Exiv2 {
                     const byte* chunkEnd = chunkStart + newPsData.size_;
                     while (chunkStart < chunkEnd) {
                         // Determine size of next chunk
-                        long chunkSize = chunkEnd - chunkStart;
+                        long chunkSize = static_cast<long>(chunkEnd - chunkStart);
                         if (chunkSize > maxChunkSize) {
                             chunkSize = maxChunkSize;
                             // Don't break at a valid IRB boundary
-                            const long writtenSize = chunkStart - newPsData.pData_;
+                            const long writtenSize = static_cast<long>(chunkStart - newPsData.pData_);
                             if (Photoshop::valid(newPsData.pData_, writtenSize + chunkSize)) {
                                 // Since an IRB has minimum size 12,
                                 // (chunkSize - 8) can't be also a IRB boundary
diff --git a/src/pngchunk_int.cpp b/src/pngchunk_int.cpp
index 08a4c4f0..bfa5546d 100644
--- a/src/pngchunk_int.cpp
+++ b/src/pngchunk_int.cpp
@@ -312,7 +312,7 @@ namespace Exiv2 {
                 const byte* pCur = psData.pData_;
                 while (   pCur < pEnd
                        && 0 == Photoshop::locateIptcIrb(pCur,
-                                                        pEnd - pCur,
+                                                        static_cast<long>(pEnd - pCur),
                                                         &record,
                                                         &sizeHdr,
                                                         &sizeIptc)) {
@@ -490,14 +490,14 @@ namespace Exiv2 {
 
     std::string PngChunk::zlibCompress(const std::string& text)
     {
-        uLongf compressedLen = (text.size() * 2); // just a starting point
+        uLongf compressedLen = static_cast<uLongf>(text.size() * 2); // just a starting point
         int zlibResult;
 
         DataBuf arr;
         do {
             arr.alloc(compressedLen);
             zlibResult = compress2(arr.pData_, &compressedLen,
-                                   (const Bytef*)text.data(), text.size(),
+                                   (const Bytef*)text.data(), static_cast<uLong>(text.size()),
                                    Z_BEST_COMPRESSION);
 
             switch (zlibResult) {
diff --git a/src/value.cpp b/src/value.cpp
index c9f4ea5f..eb85e29a 100644
--- a/src/value.cpp
+++ b/src/value.cpp
@@ -221,7 +221,7 @@ namespace Exiv2 {
     long DataValue::copy(byte* buf, ByteOrder /*byteOrder*/) const
     {
         // byteOrder not needed
-        return std::copy(value_.begin(), value_.end(), buf) - buf;
+        return static_cast<long>(std::copy(value_.begin(), value_.end(), buf) - buf);
     }
 
     long DataValue::size() const
@@ -1055,7 +1055,7 @@ namespace Exiv2 {
         tms.tm_mday = date_.day;
         tms.tm_mon = date_.month - 1;
         tms.tm_year = date_.year - 1900;
-        auto l = std::mktime(&tms);
+        long l = static_cast<long>(std::mktime(&tms));
         ok_ = (l != -1);
         return l;
     }
diff --git a/src/xmp.cpp b/src/xmp.cpp
index 5be6b393..1aaf98aa 100644
--- a/src/xmp.cpp
+++ b/src/xmp.cpp
@@ -597,7 +597,7 @@ namespace Exiv2 {
             return 2;
         }
 
-        SXMPMeta meta(xmpPacket.data(), xmpPacket.size());
+        SXMPMeta meta(xmpPacket.data(), static_cast<XMP_StringLen>(xmpPacket.size()));
         SXMPIterator iter(meta);
         std::string schemaNs, propPath, propValue;
         XMP_OptionBits opt;