diff --git a/ui-tree.c b/ui-tree.c
index 75ec9cb..0cdbf6d 100644
--- a/ui-tree.c
+++ b/ui-tree.c
@@ -67,7 +67,7 @@
 	html("<table summary='blob content' class='bin-blob'>\n");
 	html("<tr><th>ofs</th><th>hex dump</th><th>ascii</th></tr>");
 	for (ofs = 0; ofs < size; ofs += ROWLEN, buf += ROWLEN) {
-		htmlf("<tr><td class='right'>%04x</td><td class='hex'>", ofs);
+		htmlf("<tr><td class='right'>%04lx</td><td class='hex'>", ofs);
 		for (idx = 0; idx < ROWLEN && ofs + idx < size; idx++)
 			htmlf("%*s%02x",
 			      idx == 16 ? 4 : 1, "",
@@ -108,7 +108,7 @@
 	html(")\n");
 
 	if (ctx.cfg.max_blob_size && size / 1024 > ctx.cfg.max_blob_size) {
-		htmlf("<div class='error'>blob size (%dKB) exceeds display size limit (%dKB).</div>",
+		htmlf("<div class='error'>blob size (%ldKB) exceeds display size limit (%dKB).</div>",
 				size / 1024, ctx.cfg.max_blob_size);
 		return;
 	}