Compatibility summary
You will need a travel adapter in Laos; plug types used there differ from Singapore.
Plug comparison
Singapore plug types: G
Laos plug types: A B C
There is no common plug type between Singapore (G) and Laos (A B C). You need a travel adapter.
Voltage comparison
Singapore: 230V, 50Hz
Laos: 230V, 50Hz
Voltage difference is within a range many devices tolerate; check your appliance label.