The Genome Has Near Matches
A guide that matches its intended locus can still bind elsewhere. Risk depends not only on total mismatches, but where they land relative to the PAM-proximal seed.
crisprradar scans both DNA strands for 20-base protospacers beside SpCas9 NGG PAMs, compares each candidate with the guide, and reports total and seed mismatches with a transparent specificity score.
Keep Sequence Screening Local
FASTA-like sequence and guide input stay on the machine. The CLI, API, browser workbench, Docker image, and tests all execute the same scanner without an external service or API key.
The Demo
Across 149 bases, the scanner finds three candidate sites: one exact target and two off-targets. The highest-risk off-target has one mismatch, one seed mismatch, and specificity 85.
The scope is mismatch-only SpCas9 NGG screening. DNA or RNA bulges, chromatin accessibility, nuclease-specific behavior, and experimental validation are outside the claim.
Research Basis
The implementation follows the inspectable search surface used by open CRISPR off-target tools such as CRISPRitz: explicit PAM-aware candidate enumeration and mismatch reporting.
Read the CRISPRitz.