OpenAI MRCR v2 8-needle 256K-512K (MRCR v2 256K-512K)
We show this table for reference; we do not rank on it.
MRCR v2 slice focused on retrieval across 256K-512K-token contexts.
Benchmark score on MRCR v2 256K-512K — October 17, 2026
We compile the MRCR v2 256K-512K rows from provider self-reports. GPT-6 Astra leads the table at 100.0%, followed by Muse Spark 1.3 (98.5%). We do not use these results to rank models overall.
2 modelsReasoningCurrentDisplay onlyUpdated October 17, 2026
Benchmark score table (2 models)
| Rank | Model / configuration | Score | Parameters (B) | Open / closed |
|---|---|---|---|---|
| 1 | GPT-6 AstraOpenAI | 100.0% | Not reported | Closed |
| 2 | Muse Spark 1.3Meta | 98.5% | Not reported | Closed |
About MRCR v2 256K-512K
Year
2026
Tasks
100 eight-needle retrieval examples
Format
Mean sequence-matcher ratio
Difficulty
Very long-context retrieval
Meta re-bins OpenAI's MRCR v2 data by o200k_base token count and evaluates 100 examples with eight needles. The mean sequence-matcher ratio stays display-only because this slice is not part of the weighted reasoning schema.
Freshness and provenance
Version
MRCR v2 256K-512K 2026
Refresh cadence
Quarterly
Staleness state
Current
Question availability
Public benchmark set
BenchLM uses freshness metadata to decide whether a benchmark should still be treated as a strong differentiator, a benchmark to watch, or a display-only reference. For the full scoring policy, see the BenchLM methodology page.
Questions
What does MRCR v2 256K-512K measure?
MRCR v2 slice focused on retrieval across 256K-512K-token contexts.
Which model scores highest on MRCR v2 256K-512K?
GPT-6 Astra by OpenAI currently leads with a score of 100.0% on MRCR v2 256K-512K.
How many models are evaluated on MRCR v2 256K-512K?
2 AI models have published results on MRCR v2 256K-512K in the BenchLM catalog.
Compare top models on MRCR v2 256K-512K
Know when it’s worth switching models
The model to choose, the cheaper alternative, and the release we would wait on.
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