ModelRefs / RULER — AI Glossary

RULER — AI Glossary

A long-context benchmark with synthetic tasks at controlled context lengths to stress-test retrieval and reasoning across 4K–128K tokens.

Overview

RULER (Hsieh et al. 2024, NVIDIA) tests: needle in a haystack (single/multi), variable tracking, and aggregation tasks at lengths 4K, 8K, 16K, 32K, 64K, 128K. Unlike NIAH, RULER requires multi-hop retrieval and counting. Reveals that many models claiming 128K context show significant degradation beyond 32K on hard tasks.

Reference details

Topicevaluation
Last reviewed2026-06-24

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Frequently asked questions

What is RULER?

A long-context benchmark with synthetic tasks at controlled context lengths to stress-test retrieval and reasoning across 4K–128K tokens.

What concepts are related to RULER?

Closely related concepts include needle in haystack, long context, open llm leaderboard.