How accurate is Kurippu?

The short answer: Kurippu's grade is an estimate, and we have not yet measured it against expert tutors or real OET results. That study is under way, and we will publish the results here, good or bad.

How Kurippu decides a grade

• An AI model marks your letter on the six OET Writing criteria, using marking rules we wrote from OET's published graded sample letters and their official grades.
• The overall grade is then calculated from those six scores using OET's published B standard: Purpose 2 of 3 and every other criterion 5 of 7. Near the line, Kurippu says "Borderline" rather than guessing.
• Letter length is measured by Kurippu itself, not estimated by the AI.
• If you submit exactly the same letter and case notes again, you get exactly the same result.

How we test it today

We keep a set of practice letters, written for testing, with deliberately planted mistakes: wrong verb forms, informal phrases, missing care instructions, irrelevant details, a late purpose and so on. Every change to Kurippu is checked on that set before it goes live. This shows whether Kurippu finds mistakes and grades consistently. It does not prove that its grades match real OET marking.

What we are measuring next

• Agreement with experienced OET tutors. Tutors mark practice letters without seeing Kurippu's grade, and we compare. We will report how often Kurippu agrees with them on whether a letter reaches C+ and B, how often it is too generous, and how often the tutors agree with each other.
• Real results. Nurses who practise on Kurippu and then sit OET can share their Writing result, with consent, so we can check how well our estimates predicted it.

We will publish each result with the number of letters, the range of uncertainty, the method and the date. We will never quote a single "accuracy %" without them.

How to use the estimate

• Use it to find what to fix, not as a promise of your exam grade.
• If a result looks wrong, tell us. It helps us improve, and we will check it.
• Your tutor's judgement and OET's official result always come first.