| Feature | Fluke 51 | Fluke 52 | Fluke 53 | Fluke 54 |
| Thermocouple type | K, J, T, E | K, J, T, E | K, J, T, E, N, R, S | K, J, T, E, N, R, S |
| Number of inputs | Single | Dual | Single | Dual |
| Time stamp | Relative time | Relative time | Time of day | Time of day |
| Temperature measurement | Type J, K, T, E, N: ±[0.05% + 0.3°C]* |
| accuracy (temp. above -100 °C) | R and S-type: ±[0.05% + 0.4°C]* |
| Measurement range (depending on thermocouple type) | -250°C (-418°F) to1767°C (3213°F) |
| Display resolution | 0.1 °C, 0.1 K < 1000 1°C, 1 K >=1000 |
| Operating temperature | -10 °C to 50 °C |
| Storage temperature | -40 °C to 60 °C |
| Humidity | 0% to 90%; 0 °C to 35 °C |
| | 0% to 70%; 0 °C to 50 °C |
| Weight | 400 g (14 oz) |
| Size (H x W x D) | 173 mm L x 86 mm W x 38 mm |
| Battery | 3 AA batteries: typical 1000 hour life |