diff --git a/autoninja b/autoninja
index 45c71fc64..7e4a09e88 100755
--- a/autoninja
+++ b/autoninja
@@ -5,7 +5,7 @@
 # found in the LICENSE file.
 
 # Set unique build ID.
-AUTONINJA_BUILD_ID="$(python -c "import uuid; print(uuid.uuid4())")"
+AUTONINJA_BUILD_ID="$(python3 -c "import uuid; print(uuid.uuid4())")"
 export AUTONINJA_BUILD_ID
 
 if [ "$NINJA_SUMMARIZE_BUILD" == "1" ]; then
@@ -21,16 +21,16 @@ if [ "$NINJA_SUMMARIZE_BUILD" == "1" ]; then
 fi
 if eval "$command"; then
   if [ "$NINJA_SUMMARIZE_BUILD" == "1" ]; then
-    python "$(dirname -- "$0")/post_build_ninja_summary.py" "$@"
+    python3 "$(dirname -- "$0")/post_build_ninja_summary.py" "$@"
   fi
 
   # Collect ninjalog from googler.
-  python "$(dirname -- "$0")/ninjalog_uploader_wrapper.py" --cmd $command
+  python3 "$(dirname -- "$0")/ninjalog_uploader_wrapper.py" --cmd $command
   exit
 fi
 
 # Collect ninjalog from googler.
-python "$(dirname -- "$0")/ninjalog_uploader_wrapper.py" --cmd $command
+python3 "$(dirname -- "$0")/ninjalog_uploader_wrapper.py" --cmd $command
 
 # Return an error code of 1 so that if a developer types:
 # "autoninja chrome && chrome" then chrome won't run if the build fails.