Inference of CRISPR Editing (ICE) is an open-source, free to use web-based tool (https://ice.synthego.com) that quickly determines rates of CRISPR-Cas9 editing at a specific, sgRNA directed genomic location within a cell population. It can be used for analyzing CRISPR editing that involves the formation of Indels that result from a single CRISPR-Cas9 double-stranded DNA break. ICE compares standard Sanger sequencing reads of PCR amplicons from both a wild-type sequence and a CRISPR-edited locus and determines what percentage of each sequence is present. ICE then reports an Indel frequency spectrum and proposes possible CRISPR edit outcome sequences. Inference of CRISPR Editing-Decomposition (ICE-D) is used to quantify any indel mutations that are not captured by the explicit modeling of edit outcomes.