CRISPR-based gene editing holds great promise, but off-target effects remain a major concern, especially across diverse genetic backgrounds. A new study presents a web-based tool that enhances off-target site prediction by incorporating individual genetic variants. Developed using the human genome and pepper plant cultivars, the tool improves accuracy at the haplotype level. The user-friendly login-free platform offers researchers a powerful way to personalize and safeguard genome editing applications across fields.