The numbers the rest of this site is written in — with their uncertainties, and an honest note where physics disagrees with itself. Values are CODATA 2022, IAU nominal for solar quantities, and Planck 2018 / SH0ES 2022 for cosmology.
Since 2019 the SI has no artefacts and no measured base units. Seven constants are fixed by decree — assigned exact values with zero uncertainty — and every unit follows from them. The kilogram is no longer a cylinder in Paris; it is whatever makes Planck's constant come out right.
From the Constants and Units databases in Notion. Uncertainties are the standard (1σ) values; “exact” means fixed by definition, not merely well measured. The two Hubble constants are both listed on purpose — that disagreement is the Hubble tension, and pretending it away would be dishonest.