The Ensembl Variant Effect Predictor (VEP) is a powerful tool for analyzing, annotating, and prioritizing genomic variants in coding and non-coding regions. It provides extensive genomic annotation and supports various interfaces to suit different needs, with options for configuration and extension. VEP is open-source, free to use, and ensures full reproducibility of results. It simplifies and accelerates variant interpretation in various study designs, from disease investigation to population studies. VEP can handle sequence variants and larger structural variants, providing detailed annotations on transcripts, proteins, and regulatory regions. It supports multiple species and offers flexible output formats, including HTML, text, VCF, GVE, and JSON. VEP is available as an online tool, a downloadable Perl script, and via the Ensembl REST API, each optimized for different data volumes and user experience levels. The tool's performance is comparable to other tools like Annovar and SnpEff, with faster processing times for smaller datasets. VEP's algorithms and code are part of the freely available Ensembl API, coded in Perl with time-critical components written in C. VEP's caches are built for each of Ensembl's primary species, ensuring access to the latest annotation data. The tool has been widely used in large-scale projects and clinical applications, contributing to advancements in genomics research and personalized medicine.The Ensembl Variant Effect Predictor (VEP) is a powerful tool for analyzing, annotating, and prioritizing genomic variants in coding and non-coding regions. It provides extensive genomic annotation and supports various interfaces to suit different needs, with options for configuration and extension. VEP is open-source, free to use, and ensures full reproducibility of results. It simplifies and accelerates variant interpretation in various study designs, from disease investigation to population studies. VEP can handle sequence variants and larger structural variants, providing detailed annotations on transcripts, proteins, and regulatory regions. It supports multiple species and offers flexible output formats, including HTML, text, VCF, GVE, and JSON. VEP is available as an online tool, a downloadable Perl script, and via the Ensembl REST API, each optimized for different data volumes and user experience levels. The tool's performance is comparable to other tools like Annovar and SnpEff, with faster processing times for smaller datasets. VEP's algorithms and code are part of the freely available Ensembl API, coded in Perl with time-critical components written in C. VEP's caches are built for each of Ensembl's primary species, ensuring access to the latest annotation data. The tool has been widely used in large-scale projects and clinical applications, contributing to advancements in genomics research and personalized medicine.