diff --git a/Makefile b/Makefile
index 681d82601..34a7930a3 100644
--- a/Makefile
+++ b/Makefile
@@ -3,6 +3,7 @@ BUILD_DIR := build
 BUILD_TARGET := $(BUILD_DIR)/pdf.js
 DEFAULT_BROWSERS := resources/browser_manifests/browser_manifest.json
 DEFAULT_TESTS := test_manifest.json
+DEFAULT_PYTHON := python2.7
 
 EXTENSION_SRC := ./extensions/
 EXTENSION_BASE_VERSION := 4bb289ec499013de66eb421737a4dbb4a9273eda
@@ -44,7 +45,7 @@ PDF_JS_FILES = \
 # This target starts a local web server at localhost:8888. This can be
 # used for testing all browsers.
 server:
-	@cd test; python2 test.py --port=8888;
+	@cd test; $(DEFAULT_PYTHON) test.py --port=8888;
 
 # make test
 #
@@ -107,7 +108,7 @@ browser-test:
 	fi;
 
 	cd test; \
-	python2 test.py --reftest \
+	$(DEFAULT_PYTHON) test.py --reftest \
 	--browserManifestFile=$(PDF_BROWSERS) \
 	--manifestFile=$(PDF_TESTS)