# Approximate-#SAT solver

I am looking for a solver that computes an approximation to #SAT. In other words, given a formula $\phi(x)$ in CNF, approximately count the number of satisfying assignments to $\phi$. I'm interested in an approximate count, not the exact number. Are there any existing working implementations that I can download and try?

To be clear, I'm not looking for algorithms or for papers describing algorithms; I'm looking for an implementation I can use, in the style of a SAT solver. This question is related to #SAT Solver download, except that one asks for solvers that exactly count the number of satisfying assignments, whereas I am interested in solvers that approximate the number of satisfying assignments (I do not need an exact count).