Significantly older
---
The year of Gimli's birth is given in Appendix A, in the family tree for the Line of Durin, as 2879 of the Third Age (click to embiggen):

[![enter image description here][1]][2]

Appendix B gives the date of the Council of Elrond as October 25, 3018.

So Gimli is actually [almost 140][3] years old when we first meet him, and is certainly that age by the end of the trilogy.

So yes, in general, Dwarves live longer than humans do. Tolkien nowhere specifically discusses their lifespan, but in *The Peoples of Middle-earth*, Christopher Tolkien notes that Dwarves we know of (which is essentially just the people in that family tree) generally lived from 247 to 256 years, with few outliers:

>It will be found in the genealogical table that the life-span of all the 'kings of Durin's Folk' from Thrain I to Nain II varied only between 247 and 256 years, and no Dwarf in the table exceeded that, save Borin (261) and Dwalin, who lived to the vast age of 340

><sup>*History of Middle-earth* XII *The Peoples of Middle-earth* Chapter 9: "The Making of Appendix A" Notes</sup>

  [1]: https://i.sstatic.net/eik6mm.png
  [2]: https://i.sstatic.net/eik6m.png
  [3]: https://www.wolframalpha.com/input/?i=3018-2879