diff --git a/tests/Makefile b/tests/Makefile
index b020427d..1dfe19a7 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -1,6 +1,6 @@
 SYS := $(shell $(CXX) -dumpmachine)
 
-CXXFLAGS += -Wall -Wno-unused-parameter -Wextra -pedantic -O0 -g -std=c++17 -D_GLIBCXX_USE_NANOSLEEP=1 -DOPENSSL_SUPPRESS_DEPRECATED -pthread -Wl,--unresolved-symbols=ignore-in-object-files
+CXXFLAGS += -Wall -Wno-unused-parameter -Wextra -pedantic -O0 -g -std=c++20 -D_GLIBCXX_USE_NANOSLEEP=1 -DOPENSSL_SUPPRESS_DEPRECATED -pthread -Wl,--unresolved-symbols=ignore-in-object-files
 INCFLAGS += -I../libi2pd
 
 LIBI2PD = ../libi2pd.a