120V vs 240V saunas.
The voltage label is only the beginning. Circuit amperage, receptacle type, heater load and manufacturer instructions determine what installation actually requires.
Why 120V models are attractive
Some home infrared saunas—and a small number of specialized hybrid designs—operate on 120V power. That can make installation simpler when the manufacturer permits connection to an appropriate existing receptacle. “120V,” however, should not automatically be interpreted as “any outlet.” The required amperage and whether the circuit must be dedicated still matter.
Why traditional saunas are often 240V
Electric rock heaters commonly use higher power than plug-in infrared cabins. Many residential traditional sauna heaters therefore use 240V circuits and require hardwiring or a specific electrical arrangement. Heater size, room volume and local electrical code all affect the final installation.
Do not size electrical work from a comparison website
The comparison database is a research tool, not an electrical plan. Before installing a sauna, use the current installation manual for the exact model and heater configuration. Where required, have a qualified electrician confirm circuit sizing, conductor sizing, overcurrent protection and receptacle or hardwire requirements.