Mean Reciprocal Rank (MRR) Calculator
Paste the first-hit rank of each query, or a 0/1 relevance list per query, and get MRR with every reciprocal rank and the full arithmetic shown. The standard information-retrieval / TREC definition. No signup, nothing uploaded.
How it works
Mean Reciprocal Rank (MRR) measures how high up a ranked list the first relevant result appears, averaged over a set of queries. It is the headline metric for tasks that have one correct answer to find quickly, question answering, known-item search, entity lookup, and the retrieval step of a RAG pipeline. The definition here follows Voorhees (1999), who introduced MRR as the official score of the TREC-8 Question Answering track, and Manning, Raghavan & Schütze, §8.
Positions are 1-indexed. For each query i, let rankᵢ be the position of the first relevant result. The score is built in three steps:
- Reciprocal rank. Take
RRᵢ = 1 / rankᵢ. A first hit at rank 1 scores 1, rank 2 scores 0.5, rank 3 scores about 0.333, the reward drops off quickly as the first relevant result sinks lower. - No-hit convention. If a query returns no relevant result at all,
RRᵢ = 0(Voorhees, 1999). The query still counts toward Q, so misses pull the average down rather than being ignored. - Average. Add the reciprocal ranks and divide by the number of queries:
MRR = (1/Q) · Σᵢ 1/rankᵢ, a value in [0, 1].
The two input modes are equivalent. In ranks mode you type the position directly. In relevance-list mode you give a 0/1 list per query and the tool finds the first 1 from the left, so 0, 0, 1 is read as rank 3, identical to typing 3; an all-zero line is a no-hit. Because MRR depends only on the first relevant position, anything below it is irrelevant to the score, that is exactly the difference from NDCG, which grades and discounts the whole list. As a credibility check, the calculator computes the average a second way, summing the reciprocal ranks smallest-first rather than in input order, and confirms the two routes agree to floating-point precision. Everything is deterministic and runs entirely in your browser.
Worked examples
Frequently asked questions
Sources & references
- Manning, Raghavan & Schütze: Introduction to Information Retrieval, §8 Evaluation in information retrieval (Cambridge / Stanford NLP)
- E. M. Voorhees (1999): The TREC-8 Question Answering Track Report (NIST): origin of MRR and the no-relevant-result ⇒ 0 convention
- Wikipedia: Mean reciprocal rank: cross-check of the formula and notation
The formula on this page was last cross-checked against these sources on 2026-06-10. MRR is a stable mathematical definition, so this tool needs no rate or schedule updates, only the worked examples are periodically re-reconciled.
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