diff --git a/core/net/url.odin b/core/net/url.odin
index 29028b16c..1a8028ad0 100644
--- a/core/net/url.odin
+++ b/core/net/url.odin
@@ -114,6 +114,8 @@ join_url :: proc(scheme, host, path: string, queries: map[string]string, fragmen
 }
 
 percent_encode :: proc(s: string, allocator := context.allocator) -> string {
+	HEX_DIGITS_UPPER := "0123456789ABCDEF" // NOTE(michtesar): RFC 3986 §2.1
+
 	b := strings.builder_make(allocator)
 	strings.builder_grow(&b, len(s) + 16) // NOTE(tetra): A reasonable number to allow for the number of things we need to escape.
 
@@ -124,10 +126,9 @@ percent_encode :: proc(s: string, allocator := context.allocator) -> string {
 		case:
 			bytes, n := utf8.encode_rune(ch)
 			for byte in bytes[:n] {
-				buf: [2]u8 = ---
-				t := strconv.write_int(buf[:], i64(byte), 16)
-				strings.write_rune(&b, '%')
-				strings.write_string(&b, t)
+				strings.write_byte(&b, '%')
+				strings.write_byte(&b, HEX_DIGITS_UPPER[byte >> 4])
+				strings.write_byte(&b, HEX_DIGITS_UPPER[byte & 0xF])
 			}
 		}
 	}