structured output benchmark
IFEval
Instruction-Following Evaluation (IFEval) benchmark for large language models, focusing on verifiable instructions with 25 types of instructions and around 500 prompts containing one or more verifiable constraints
Updated Aug 7, 2026
Published models65
Registry coverage65
MetricScore
EvidenceB
IFEval leaderboard
Sorted by the source-provided rank. Higher score is better according to the registry.
Score distribution
Top published rows on the benchmark's original scale.
IFEval highlights
The top published results on this benchmark's own scale.
What is IFEval?
Definition and scoring fields from the benchmark registry.
Instruction-Following Evaluation (IFEval) benchmark for large language models, focusing on verifiable instructions with 25 types of instructions and around 500 prompts containing one or more verifiable constraints
Scores are shown in ratio. The current registry marks this benchmark as not independently verified with evidence level B.
- Family
- IFEval
- Modality
- text
- Primary category
- structured output
- Score direction
- higher
- LLMBoard eligible
- Yes
- Evaluation key
- ifeval|llm-stats-current
Source-native results are preserved. Eligibility for the overall LLMBoard score is a separate policy decision.
FAQ
Common questions about IFEval.
Which model scores highest on IFEval?
Qwen3.5-27B is currently ranked first with 95.0%.
What does IFEval measure?
Instruction-Following Evaluation (IFEval) benchmark for large language models, focusing on verifiable instructions with 25 types of instructions and around 500 prompts containing one or more verifiable constraints
Is a higher score better?
Yes. Higher values rank better for this benchmark.
How many models are compared?
65 unique published model results are currently shown.
Does this benchmark affect the overall score?
This benchmark is marked as eligible for the current LLMBoard capability methodology.