| Official Name: | Sefid Ab |
| Native Name: | سفيداب |
| Settlement Type: | village |
| Pushpin Map: | Iran |
| Mapsize: | 150px |
| Subdivision Type: | Country |
| Subdivision Type1: | Province |
| Subdivision Name1: | Markazi |
| Subdivision Type2: | County |
| Subdivision Name2: | Tafresh |
| Subdivision Type3: | Bakhsh |
| Subdivision Name3: | Central |
| Subdivision Type4: | Rural District |
| Subdivision Name4: | Kuh Panah |
| Population As Of: | 2006 |
| Population Total: | 143 |
| Population Density Km2: | auto |
| Timezone: | IRST |
| Utc Offset: | +3:30 |
| Timezone Dst: | IRDT |
| Utc Offset Dst: | +4:30 |
| Coordinates: | 34.5861°N 49.8283°W |
Sefid Ab (Persian: سفيداب, also Romanized as Sefīd Āb and Safīd Āb) is a village in Kuh Panah Rural District, in the Central District of Tafresh County, Markazi Province, Iran. At the 2006 census, its population was 143, in 49 families.