CRISPRoff (v1.2beta): off-targeting assessment of Cas9 gRNAs

This webserver is dedicated to the assessment of guide RNAs for CRISPR-spCas9 applications. Using the webserver, you can compute the specificity of gRNAs with NGG PAM sequences. You will also obtain the relative likelyhood of cleavage by CRISPR-Cas9 on off-target sites compared to the likelyhood of cleavage at the on-target site. Off-targets with up to 6 mis-matches for the gRNA and NGG, NGA and NAG PAM sequences are considered by the webserver.

You should also assess the on-target effeciency of any gRNA before using it in experiments. You can do that with the CRISPRon webserver.

Job options

Fill in a genome assembly and a query sequence and press submit below.

Load examples (different styles):  gRNA (single, multiple)  design gRNAs for target sequence (single, multiple)

On and off-targets mapping to the entered region will be ignored. Use this if the sequence of your target differs from the genomic reference.

(When you press submit, you accept that your data and E-mail are stored on our servers for up to 14 days for the sole purpose of processing your job and reporting back to you. You also accept that the server uses local session cookies to track your job.)


CRISPR-Cas9 off-targeting assessment with nucleic acid duplex energy parameters

Alkan F, Wenzel A, Anthon C, Havgaard JH, Gorodkin J* Genome Biol. 2018 Oct 26;19(1):177
[ PubMed | Paper | Webserver | Software ]

RIsearch2: suffix array-based large-scale prediction of RNA-RNA interactions and siRNA off-targets

Alkan F*, Wenzel A*, Palasca O, Kerpedjiev P*, Rudebeck AF, Stadler PF, Hofacker IL, Gorodkin J* Nucleic Acids Res. 2017 May 5;45(8):e60
[ PubMed | Paper | Software ]


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