The ITS (International Temperature Scale) uses 17 temperature reference points:
| Element | Symbol | Type | K | °C |
| Helium | He | Vapour pressure | 5 | -268.15 |
| Hydrogen | H2 | Triple point | 13.8033 | -259.3467 |
| Hydrogen | H2 | Vapour pressure | 17 | -256.15 |
| Hydrogen | H2 | Vapour pressure | 20.3 | -252.85 |
| Neon | Ne | Triple point | 24.5561 | -248.5939 |
| Oxygen | O2 | Triple point | 54.3584 | -218.7916 |
| Argon | Ar | Triple point | 83.8058 | -189.3442 |
| Mercury | Hg | Triple point | 234.315 | -38.8344 |
| Water | H2O | Triple point | 273.16 | 0.01 |
| Gallium | Ga | Melting | 302.9146 | 29.7646 |
| Indium | In | Freezing | 429.7485 | 156.5985 |
| Tin | Sn | Freezing | 505.078 | 231.928 |
| Zinc | Zn | Freezing | 692.677 | 419.527 |
| Aluminium | Al | Solidification | 933.473 | 660.323 |
| Silver | Ag | Freezing | 1234.93 | 961.78 |
| Gold | Au | Freezing | 1337.33 | 1064.18 |
| Copper | Cu | Freezing | 1357.77 | 1084.62 |
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