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Our aim is to derive a self-consistent age, distance and composition for theglobular cluster $47\,$Tucanae ($47\,$Tuc; NGC104). First, we reevaluate thereddening towards the cluster resulting in a nominal $E(B-V)=0.03\pm0.01$ asthe best estimate. The $T_{\rm eff}$ of the components of the eclipsing binarymember V69 is found to be $5900\pm72$ K from both photometric and spectroscopicevidence. This yields a true distance modulus $(m-M)_0=13.21\pm0.06$(random)$\pm0.03 $(systematic) to $47\,$Tuc when combined with existing measurements ofV69 radii and luminosity ratio. We then present a new completelyself-consistent isochrone fitting method to ground based and $\textit{HST}$cluster colour-magnitude diagrams and the eclipsing binary member V69. Theanalysis suggests that the composition of V69, and by extension one of thepopulations of $47\,$Tuc, is given by [Fe/H]$\sim-0.70$, [O/Fe]$\sim+0.60$, and$Y\sim0.250$ on the solar abundance scale of Asplund, Grevesse & Sauval.However, this depends on the accuracy of the model $T_{\rm eff}$ scale which is50-75 K cooler than our best estimate but within measurement uncertainties. Ourbest estimate of the age of $47\,$Tuc is 11.8 Gyr, with firm ($3 \sigma$) lowerand upper limits of 10.4 and 13.4 Gyr, respectively, in satisfactory agreementwith the age derived from the white dwarf cooling sequence if our determinationof the distance modulus is adopted.

The age of 47Tuc from self-consistent isochrone fits to colour-magnitude diagrams and the eclipsing member V69