  The ropelength of a knot is the minimum length required to tie it.
Computational upper bounds have previously been computed for every prime knot
with up to 11 crossings. Here, we present ropelength measurements for the 2176
knots with 12 crossings, of which 1288 are alternating and 888 are
non-alternating. We report on the distribution of ropelengths within and
between crossing numbers, as well as the space writhe of the tight knot
configurations. It was previously established that tight alternating knots have
a ``quantized'' space writhe close to a multiple of 4/7. Our data supports this
for 12-crossing alternating knots and we find that non-alternating knots also
show evidence of writhe quantization, falling near integer or half-integer
multiples of 4/3, depending on the parity of the crossing number. Finally, we
examine correlations between geometric properties and topological invariants of
tight knots, finding that the ropelength is positively correlated with
hyperbolic volume and its correlates, and that the space writhe is positively
correlated with the Rasmussen s invariant.
