Turnitin duplicate checking rate: Some schools stipulate that the repetition rate and citation rate are below 30%, while others stipulate that they are below 20%. Turnitin, as the duplicate checking system of school papers, can check the duplicate checking rate of students' papers. Some schools stipulate that the repetition rate and citation rate are below 30%, while others stipulate that they are below 20%, but not most schools stipulate that they are below 10%.