WebSTR: a population-wide database of short tandem repeat variation in humans

WebSTR contains population and genome-wide information about genetic variation and other characteristics of short tandem repeats (STRs) in humans including:

Expression STRs in GTEx (see Fotsing et al.)
STR imputation metrics (see Saini et al.)
STR mutation rates and constraint scores (see Gymrek et al.)
Per-cohort allele frequencies at each STR

The about page describes the datasets in detail and a brief tutorial to help you get started.