diff --git a/meson.build b/meson.build
index 6b50ba03..6dc4d098 100644
--- a/meson.build
+++ b/meson.build
@@ -224,7 +224,7 @@ executable(
   'tokenize.c', 'tokenize.h',
   'url-mode.c', 'url-mode.h',
   'user-notification.c', 'user-notification.h',
-  'wayland.c', 'wayland.h',
+  'wayland.c', 'wayland.h', 'shm-formats.h',
   wl_proto_src + wl_proto_headers, version,
   dependencies: [math, threads, libepoll, pixman, wayland_client, wayland_cursor, xkb, fontconfig, utf8proc,
                  tllist, fcft],
diff --git a/shm-formats.h b/shm-formats.h
new file mode 100644
index 00000000..bb49bd94
--- /dev/null
+++ b/shm-formats.h
@@ -0,0 +1,117 @@
+#pragma once
+
+#if defined(_DEBUG)
+static const struct shm_formats {
+    uint32_t format;
+    const char *description;
+} shm_formats[] = {
+    {WL_SHM_FORMAT_ARGB8888, "ARGB8888"},
+    {WL_SHM_FORMAT_XRGB8888, "XRGB8888"},
+    {WL_SHM_FORMAT_C8, "C8"},
+    {WL_SHM_FORMAT_RGB332, "RGB332"},
+    {WL_SHM_FORMAT_BGR233, "BGR233"},
+    {WL_SHM_FORMAT_XRGB4444, "XRGB4444"},
+    {WL_SHM_FORMAT_XBGR4444, "XBGR4444"},
+    {WL_SHM_FORMAT_RGBX4444, "RGBX4444"},
+    {WL_SHM_FORMAT_BGRX4444, "BGRX4444"},
+    {WL_SHM_FORMAT_ARGB4444, "ARGB4444"},
+    {WL_SHM_FORMAT_ABGR4444, "ABGR4444"},
+    {WL_SHM_FORMAT_RGBA4444, "RGBA4444"},
+    {WL_SHM_FORMAT_BGRA4444, "BGRA4444"},
+    {WL_SHM_FORMAT_XRGB1555, "XRGB1555"},
+    {WL_SHM_FORMAT_XBGR1555, "XBGR1555"},
+    {WL_SHM_FORMAT_RGBX5551, "RGBX5551"},
+    {WL_SHM_FORMAT_BGRX5551, "BGRX5551"},
+    {WL_SHM_FORMAT_ARGB1555, "ARGB1555"},
+    {WL_SHM_FORMAT_ABGR1555, "ABGR1555"},
+    {WL_SHM_FORMAT_RGBA5551, "RGBA5551"},
+    {WL_SHM_FORMAT_BGRA5551, "BGRA5551"},
+    {WL_SHM_FORMAT_RGB565, "RGB565"},
+    {WL_SHM_FORMAT_BGR565, "BGR565"},
+    {WL_SHM_FORMAT_RGB888, "RGB888"},
+    {WL_SHM_FORMAT_BGR888, "BGR888"},
+    {WL_SHM_FORMAT_XBGR8888, "XBGR8888"},
+    {WL_SHM_FORMAT_RGBX8888, "RGBX8888"},
+    {WL_SHM_FORMAT_BGRX8888, "BGRX8888"},
+    {WL_SHM_FORMAT_ABGR8888, "ABGR8888"},
+    {WL_SHM_FORMAT_RGBA8888, "RGBA8888"},
+    {WL_SHM_FORMAT_BGRA8888, "BGRA8888"},
+    {WL_SHM_FORMAT_XRGB2101010, "XRGB2101010"},
+    {WL_SHM_FORMAT_XBGR2101010, "XBGR2101010"},
+    {WL_SHM_FORMAT_RGBX1010102, "RGBX1010102"},
+    {WL_SHM_FORMAT_BGRX1010102, "BGRX1010102"},
+    {WL_SHM_FORMAT_ARGB2101010, "ARGB2101010"},
+    {WL_SHM_FORMAT_ABGR2101010, "ABGR2101010"},
+    {WL_SHM_FORMAT_RGBA1010102, "RGBA1010102"},
+    {WL_SHM_FORMAT_BGRA1010102, "BGRA1010102"},
+    {WL_SHM_FORMAT_YUYV, "YUYV"},
+    {WL_SHM_FORMAT_YVYU, "YVYU"},
+    {WL_SHM_FORMAT_UYVY, "UYVY"},
+    {WL_SHM_FORMAT_VYUY, "VYUY"},
+    {WL_SHM_FORMAT_AYUV, "AYUV"},
+    {WL_SHM_FORMAT_NV12, "NV12"},
+    {WL_SHM_FORMAT_NV21, "NV21"},
+    {WL_SHM_FORMAT_NV16, "NV16"},
+    {WL_SHM_FORMAT_NV61, "NV61"},
+    {WL_SHM_FORMAT_YUV410, "YUV410"},
+    {WL_SHM_FORMAT_YVU410, "YVU410"},
+    {WL_SHM_FORMAT_YUV411, "YUV411"},
+    {WL_SHM_FORMAT_YVU411, "YVU411"},
+    {WL_SHM_FORMAT_YUV420, "YUV420"},
+    {WL_SHM_FORMAT_YVU420, "YVU420"},
+    {WL_SHM_FORMAT_YUV422, "YUV422"},
+    {WL_SHM_FORMAT_YVU422, "YVU422"},
+    {WL_SHM_FORMAT_YUV444, "YUV444"},
+    {WL_SHM_FORMAT_YVU444, "YVU444"},
+    {WL_SHM_FORMAT_R8, "R8"},
+    {WL_SHM_FORMAT_R16, "R16"},
+    {WL_SHM_FORMAT_RG88, "RG88"},
+    {WL_SHM_FORMAT_GR88, "GR88"},
+    {WL_SHM_FORMAT_RG1616, "RG1616"},
+    {WL_SHM_FORMAT_GR1616, "GR1616"},
+    {WL_SHM_FORMAT_XRGB16161616F, "XRGB16161616F"},
+    {WL_SHM_FORMAT_XBGR16161616F, "XBGR16161616F"},
+    {WL_SHM_FORMAT_ARGB16161616F, "ARGB16161616F"},
+    {WL_SHM_FORMAT_ABGR16161616F, "ABGR16161616F"},
+    {WL_SHM_FORMAT_XYUV8888, "XYUV8888"},
+    {WL_SHM_FORMAT_VUY888, "VUY888"},
+    {WL_SHM_FORMAT_VUY101010, "VUY101010"},
+    {WL_SHM_FORMAT_Y210, "Y210"},
+    {WL_SHM_FORMAT_Y212, "Y212"},
+    {WL_SHM_FORMAT_Y216, "Y216"},
+    {WL_SHM_FORMAT_Y410, "Y410"},
+    {WL_SHM_FORMAT_Y412, "Y412"},
+    {WL_SHM_FORMAT_Y416, "Y416"},
+    {WL_SHM_FORMAT_XVYU2101010, "XVYU2101010"},
+    {WL_SHM_FORMAT_XVYU12_16161616, "XVYU12_16161616"},
+    {WL_SHM_FORMAT_XVYU16161616, "XVYU16161616"},
+    {WL_SHM_FORMAT_Y0L0, "Y0L0"},
+    {WL_SHM_FORMAT_X0L0, "X0L0"},
+    {WL_SHM_FORMAT_Y0L2, "Y0L2"},
+    {WL_SHM_FORMAT_X0L2, "X0L2"},
+    {WL_SHM_FORMAT_YUV420_8BIT, "YUV420_8BIT"},
+    {WL_SHM_FORMAT_YUV420_10BIT, "YUV420_10BIT"},
+    {WL_SHM_FORMAT_XRGB8888_A8, "XRGB8888_A8"},
+    {WL_SHM_FORMAT_XBGR8888_A8, "XBGR8888_A8"},
+    {WL_SHM_FORMAT_RGBX8888_A8, "RGBX8888_A8"},
+    {WL_SHM_FORMAT_BGRX8888_A8, "BGRX8888_A8"},
+    {WL_SHM_FORMAT_RGB888_A8, "RGB888_A8"},
+    {WL_SHM_FORMAT_BGR888_A8, "BGR888_A8"},
+    {WL_SHM_FORMAT_RGB565_A8, "RGB565_A8"},
+    {WL_SHM_FORMAT_BGR565_A8, "BGR565_A8"},
+    {WL_SHM_FORMAT_NV24, "NV24"},
+    {WL_SHM_FORMAT_NV42, "NV42"},
+    {WL_SHM_FORMAT_P210, "P210"},
+    {WL_SHM_FORMAT_P010, "P010"},
+    {WL_SHM_FORMAT_P012, "P012"},
+    {WL_SHM_FORMAT_P016, "P016"},
+    {WL_SHM_FORMAT_AXBXGXRX106106106106, "AXBXGXRX106106106106"},
+    {WL_SHM_FORMAT_NV15, "NV15"},
+    {WL_SHM_FORMAT_Q410, "Q410"},
+    {WL_SHM_FORMAT_Q401, "Q401"},
+    {WL_SHM_FORMAT_XRGB16161616, "XRGB16161616"},
+    {WL_SHM_FORMAT_XBGR16161616, "XBGR16161616"},
+    {WL_SHM_FORMAT_ARGB16161616, "ARGB16161616"},
+    {WL_SHM_FORMAT_ABGR16161616, "ABGR16161616"},
+};
+#endif
diff --git a/wayland.c b/wayland.c
index b15cd491..850b657b 100644
--- a/wayland.c
+++ b/wayland.c
@@ -27,6 +27,7 @@
 #include "render.h"
 #include "selection.h"
 #include "shm.h"
+#include "shm-formats.h"
 #include "util.h"
 #include "xmalloc.h"
 
@@ -227,6 +228,22 @@ static void
 shm_format(void *data, struct wl_shm *wl_shm, uint32_t format)
 {
     struct wayland *wayl = data;
+
+#if defined(_DEBUG)
+    bool have_description = false;
+
+    for (size_t i = 0; i < ALEN(shm_formats); i++) {
+        if (shm_formats[i].format == format) {
+            LOG_DBG("shm: 0x%08x: %s", format, shm_formats[i].description);
+            have_description = true;
+            break;
+        }
+    }
+
+    if (!have_description)
+        LOG_DBG("shm: 0x%08x: unknown", format);
+#endif
+
     if (format == WL_SHM_FORMAT_ARGB8888)
         wayl->have_argb8888 = true;
 }