gkmQC is a sequence-based computational tool for assessing and refining the quality of chromatin accessibility data using gkm-SVM. It uses the overall “predictability” of the peaks/regions as a metric of the data quality. It trains a support vector classifier (SVC) using gapped-kmer kernels (Ghandi et al., 2014; Lee, 2016), and learns DNA sequence features predictive of regulatory element activities. It can also be used to optimize a peak calling threshold, which is particularly useful for rare cell types from single-cell ATAC-seq data.