diff --git a/stb_image.h b/stb_image.h
index 9eedabedc..35a8a23b2 100644
--- a/stb_image.h
+++ b/stb_image.h
@@ -1817,7 +1817,7 @@ static stbi__uint16 *stbi__convert_format16(stbi__uint16 *data, int img_n, int r
    if (req_comp == img_n) return data;
    STBI_ASSERT(req_comp >= 1 && req_comp <= 4);
 
-   good = (stbi__uint16 *) stbi__malloc(req_comp * x * y * 2);
+   good = (stbi__uint16 *) stbi__malloc((size_t)req_comp * x * y * 2);
    if (good == NULL) {
       STBI_FREE(data);
       return (stbi__uint16 *) stbi__errpuc("outofmem", "Out of memory");
@@ -4821,7 +4821,7 @@ static int stbi__create_png_image_raw(stbi__png *a, stbi_uc *raw, stbi__uint32 r
             stbi__create_png_alpha_expand8(dest, dest, x, img_n);
       } else if (depth == 8) {
          if (img_n == out_n)
-            memcpy(dest, cur, x*img_n);
+            memcpy(dest, cur, (size_t)x * (size_t)img_n);
          else
             stbi__create_png_alpha_expand8(dest, cur, x, img_n);
       } else if (depth == 16) {
@@ -6201,7 +6201,7 @@ static void *stbi__psd_load(stbi__context *s, int *x, int *y, int *comp, int req
       out = (stbi_uc *) stbi__malloc_mad3(8, w, h, 0);
       ri->bits_per_channel = 16;
    } else
-      out = (stbi_uc *) stbi__malloc(4 * w*h);
+      out = (stbi_uc *) stbi__malloc(4 * (size_t)w * (size_t)h);
 
    if (!out) return stbi__errpuc("outofmem", "Out of memory");
    pixelCount = w*h;
@@ -6524,7 +6524,7 @@ static void *stbi__pic_load(stbi__context *s,int *px,int *py,int *comp,int req_c
    // intermediate buffer is RGBA
    result = (stbi_uc *) stbi__malloc_mad3(x, y, 4, 0);
    if (!result) return stbi__errpuc("outofmem", "Out of memory");
-   memset(result, 0xff, x*y*4);
+   memset(result, 0xff, (size_t)x * (size_t)y * 4);
 
    if (!stbi__pic_load_core(s,x,y,comp, result)) {
       STBI_FREE(result);
@@ -6833,11 +6833,11 @@ static stbi_uc *stbi__gif_load_next(stbi__context *s, stbi__gif *g, int *comp, i
       }
 
       // background is what out is after the undoing of the previou frame;
-      memcpy( g->background, g->out, 4 * g->w * g->h );
+      memcpy( g->background, g->out, 4 * (size_t)g->w * (size_t)g->h );
    }
 
    // clear my history;
-   memset( g->history, 0x00, g->w * g->h );        // pixels that were affected previous frame
+   memset( g->history, 0x00, (size_t)g->w * (size_t)g->h );        // pixels that were affected previous frame
 
    for (;;) {
       int tag = stbi__get8(s);
@@ -6991,7 +6991,7 @@ static void *stbi__load_gif_main(stbi__context *s, int **delays, int *x, int *y,
             stride = g.w * g.h * 4;
 
             if (out) {
-               void *tmp = (stbi_uc*) STBI_REALLOC_SIZED( out, out_size, layers * stride );
+               void *tmp = (stbi_uc*) STBI_REALLOC_SIZED( out, out_size, (size_t)layers * (size_t)stride );
                if (!tmp)
                   return stbi__load_gif_main_outofmem(&g, out, delays);
                else {
@@ -7007,7 +7007,7 @@ static void *stbi__load_gif_main(stbi__context *s, int **delays, int *x, int *y,
                   delays_size = layers * sizeof(int);
                }
             } else {
-               out = (stbi_uc*)stbi__malloc( layers * stride );
+               out = (stbi_uc*)stbi__malloc( (size_t)layers * (size_t)stride );
                if (!out)
                   return stbi__load_gif_main_outofmem(&g, out, delays);
                out_size = layers * stride;
diff --git a/stb_image_write.h b/stb_image_write.h
index e4b32ed1b..1db82dc44 100644
--- a/stb_image_write.h
+++ b/stb_image_write.h
@@ -141,6 +141,7 @@
       github:ignotion
       Adam Schackart
       Andrew Kensler
+      Thomas Debesse
 
 LICENSE
 
@@ -826,7 +827,7 @@ STBIWDEF int stbi_write_hdr(char const *filename, int x, int y, int comp, const
 static void *stbiw__sbgrowf(void **arr, int increment, int itemsize)
 {
    int m = *arr ? 2*stbiw__sbm(*arr)+increment : increment+1;
-   void *p = STBIW_REALLOC_SIZED(*arr ? stbiw__sbraw(*arr) : 0, *arr ? (stbiw__sbm(*arr)*itemsize + sizeof(int)*2) : 0, itemsize * m + sizeof(int)*2);
+   void *p = STBIW_REALLOC_SIZED(*arr ? stbiw__sbraw(*arr) : 0, *arr ? (stbiw__sbm(*arr)*itemsize + sizeof(int)*2) : 0, (size_t)itemsize * (size_t)m + sizeof(int)*2);
    STBIW_ASSERT(p);
    if (p) {
       if (!*arr) ((int *) p)[1] = 0;
@@ -1100,7 +1101,7 @@ static void stbiw__encode_png_line(unsigned char *pixels, int stride_bytes, int
    int signed_stride = stbi__flip_vertically_on_write ? -stride_bytes : stride_bytes;
 
    if (type==0) {
-      memcpy(line_buffer, z, width*n);
+      memcpy(line_buffer, z, (size_t)width * (size_t)n);
       return;
    }
 
@@ -1141,8 +1142,8 @@ STBIWDEF unsigned char *stbi_write_png_to_mem(const unsigned char *pixels, int s
       force_filter = -1;
    }
 
-   filt = (unsigned char *) STBIW_MALLOC((x*n+1) * y); if (!filt) return 0;
-   line_buffer = (signed char *) STBIW_MALLOC(x * n); if (!line_buffer) { STBIW_FREE(filt); return 0; }
+   filt = (unsigned char *) STBIW_MALLOC(((size_t)x * (size_t)n + 1) * (size_t)y); if (!filt) return 0;
+   line_buffer = (signed char *) STBIW_MALLOC((size_t)x * (size_t)n); if (!line_buffer) { STBIW_FREE(filt); return 0; }
    for (j=0; j < y; ++j) {
       int filter_type;
       if (force_filter > -1) {
@@ -1169,8 +1170,8 @@ STBIWDEF unsigned char *stbi_write_png_to_mem(const unsigned char *pixels, int s
          }
       }
       // when we get here, filter_type contains the filter type, and line_buffer contains the data
-      filt[j*(x*n+1)] = (unsigned char) filter_type;
-      STBIW_MEMMOVE(filt+j*(x*n+1)+1, line_buffer, x*n);
+      filt[(size_t)j * ((size_t)x * (size_t)n + 1)] = (unsigned char) filter_type;
+      STBIW_MEMMOVE(filt + (size_t)j * ((size_t)x * (size_t)n + 1) + 1, line_buffer, (size_t)x * (size_t)n);
    }
    STBIW_FREE(line_buffer);
    zlib = stbi_zlib_compress(filt, y*( x*n+1), &zlen, stbi_write_png_compression_level);