FACTS Grounding
Long-form responses must be fully grounded in a provided document. Judged by LLM panels for grounding and eligibility.
Public split of 3,513 examples plus a private evaluation set.
In the authors’ words
We introduce FACTS Grounding, an online leaderboard and associated benchmark that evaluates language models' ability to generate text that is factually accurate with respect to given context in the user prompt. In our benchmark, each prompt includes a user request and a full document, with a maximum length of 32k tokens, requiring long-form responses. The long-form responses are required to be fully grounded in the provided context document while fulfilling the user request. Models are evaluated using automated judge models in two phases: (1) responses are disqualified if they do not fulfill the user request; (2) they are judged as accurate if the response is fully grounded in the provided document. The automated judge models were comprehensively evaluated against a held-out test-set to pick the best prompt template, and the final factuality score is an aggregate of multiple judge models to mitigate evaluation bias. The FACTS Grounding leaderboard will be actively maintained over time, and contains both public and private splits to allow for external participation while guarding the integrity of the leaderboard. It can be found at https://www.kaggle.com/facts-leaderboard.
- Level
- University Undergraduates and entry-level professionals
- Scored
- Graded by a model A language model scores each response, usually against a rubric.
- Answers
- Open-ended Free-form text, documents, designs or media judged as a whole.
Kimi K2 leads with 88.5%
Best score per model as labs report them in their own cards. Labs pick their own settings, so these compare less cleanly than independent runs.
- 88.5 Kimi K2
- 87.8
Gemini 2.5 Pro
- 87.5
Gemini 2.5 Flash
- 87.5
Gemini 2.5 Flash-Lite
- 86.8
Gemini 2.5 Flash-Lite
- 85.3
Gemini 2.5 Flash
- 84.6
Gemini 2.0 Flash
- 83.6
Gemini 2.0 Flash
- 83.6
Gemini 2.0 Flash-Lite
- 82.8
Gemini 2.0 Pro
- 79.0
Gemini 4 Argon
- 75.8
Gemma 3 12B
- 74.9
Gemma 3 27B
- 70.1
Gemma 3 4B
- 36.4
Gemma 3 1B
- 1 Kimi K2 Jul 2025 88.5%
- 2
Gemini 2.5 Pro Jun 2025 87.8%
- 3
Gemini 2.5 Flash Sep 2025 87.5%
- 4
Gemini 2.5 Flash-Lite Sep 2025 87.5%
- 5
Gemini 2.5 Flash-Lite Jun 2025 86.8%
- 6
Gemini 2.5 Flash Jun 2025 85.3%
- 7
Gemini 2.0 Flash Feb 2025 84.6%
- 8
Gemini 2.0 Flash Dec 2024 83.6%
- 9
Gemini 2.0 Flash-Lite 83.6%
- 10
Gemini 2.0 Pro 82.8%
- 11
Gemini 4 Argon 79%
- 12
Gemma 3 12B 75.8%
- 13
Gemma 3 27B 74.9%
- 14
Gemma 3 4B 70.1%
- 15
Gemma 3 1B 36.4%
| # | Model | Score | Setting | Date | Source |
|---|---|---|---|---|---|
| 1 | Kimi K2 Jul 2025 | 88.5% | Jul 2025 | Model card | |
| 2 | | 87.8% | Jun 2025 | Model card | |
| 3 | | 87.5% | Sep 2025 | Model card | |
| 4 | | 87.5% | Sep 2025 | Model card | |
| 5 | | 86.8% | Jun 2025 | Model card | |
| 6 | | 85.3% | Jun 2025 | Model card | |
| 7 | | 84.6% | Feb 2025 | Model card | |
| 8 | | 83.6% | Dec 2024 | Model card | |
| 9 | | 83.6% | Feb 2025 | Model card | |
| 10 | | 82.8% | Feb 2025 | Model card | |
| 11 | | 79% | Oct 2026 | Model card | |
| 12 | | 75.8% | Mar 2025 | Model card | |
| 13 | | 74.9% | Mar 2025 | Model card | |
| 14 | | 70.1% | Mar 2025 | Model card | |
| 15 | | 36.4% | Mar 2025 | Model card |
The benchmark's own leaderboard has 35 entries, 34 of them models we track. We plot every source in the charts below.
3 models have held number one since its release in Jan 2025
Lab claims count from the day the card came out, independent runs from the model’s release. We draw one row each for the benchmark’s own leaderboard and what labs claim in their cards.
The best score passed 85% in Feb 2025
All the scores we have, one dot each, so a model tested at several settings appears more than once.
Labs dropped it from launch posts once the best score passed 85%
Launch posts from every lab that has listed it, one tick per post. Tall colored ticks include it, and short gray ones leave it out.
| Date | Launch post | Score | As the post writes it |
|---|---|---|---|
| 25 Sep 2025 | 87.5 | FACTS Grounding, Thinking | |
| 25 Sep 2025 | 87.5 | FACTS Grounding, model card | |
| 17 Jun 2025 | 85.3 | FACTS Grounding | |
| 17 Jun 2025 | 86.8 | FACTS Grounding, Thinking | |
| 17 Jun 2025 | 87.8 | FACTS Grounding | |
| 12 Mar 2025 | 74.9 | FACTS Grounding (IT) | |
| 5 Feb 2025 | 83.6 | FACTS Grounding | |
| 5 Feb 2025 | 84.6 | FACTS Grounding | |
| 5 Feb 2025 | 82.8 | FACTS Grounding | |
| 11 Dec 2024 | 83.6 | FACTS Grounding |
11 system cards report it, from 2 labs
Besides launch posts, we read the system cards, model cards and technical reports labs publish with a release. They report far more, including safety and frontier-risk tests.
| Date | Document | Score | As the document writes it | Section |
|---|---|---|---|---|
| 13 Oct 2026 | | 79 | FACTS Grounding factuality score 79.0% (Figure 5.13) | Hallucination |
| 26 Sep 2025 | | 87.5 | Factuality FACTS Grounding (Table, pp.4 to 5) | Hallucination |
| 21 Jul 2025 | Kimi K2 technical report | 88.5 | FACTS Grounding (Adjusted) (Table 3) | Hallucination |
| 7 Jul 2025 | | 87.8 | FACTS Grounding (Table 3) | Capabilities |
| 7 Jul 2025 | | 85.3 | FACTS Grounding (Table 3) | Capabilities |
| 15 Apr 2025 | | 84.6 | FACTS Grounding (Table, p.3, column Gemini 2.0 Flash (GA)) | Capabilities |
| 10 Apr 2025 | | 83.6 | FACTS Grounding (Table, p.3) | Capabilities |
| 25 Mar 2025 | | 70.1 | FACTS Grounding, IT, zero-shot (Table 6) | Capabilities |
| 25 Mar 2025 | | 74.9 | FACTS Grounding, IT, zero-shot (Table 6) | Capabilities |
| 25 Mar 2025 | | 36.4 | FACTS Grounding, IT, zero-shot (Table 6) | Capabilities |
| 25 Mar 2025 | | 75.8 | FACTS Grounding, IT, zero-shot (Table 6) | Capabilities |
Versions
We switch the top row to each new version when it comes out. Open it for one row per version. An old version stays in play while people still test it, so whoever first takes it past 85% gets credit for closing it out.
More in Factuality
- SimpleVQA In use Models answer 2,025 short factual questions about images across 9 tasks and 9 topics. An LLM judge grades answers against fixed references.
Qwen3.7-Plus 81.7%
- HallusionBench In use Models answer 1,129 yes or no questions about 346 images, built in pairs to expose language hallucination and visual illusion. Scored by accuracy.
Keye-VL-2.0-30B-A3B 73.5%
- SimpleQA Verified In use 1,000 human-verified, de-duplicated short-answer factual questions measuring parametric knowledge.
Gemini 3.1 Pro 77.5%
- GaRAGe In use Models write long-form RAG answers to 2,366 questions with human-annotated grounding passages. Scoring checks whether answers use the relevant passages.
Nemotron 3.5 Bolt E4B 40.7%
- Kimi Hallu Bench In use Models answer hard prompts drawn from practical work tasks. Fact-checking agents score the share of claims that are hallucinated. Kimi K3.1 Pro 8.30%
- RAGTruth In use A word-level annotated corpus of hallucinations in retrieval-augmented generation answers. It is used to train and evaluate hallucination detection and RAG faithfulness.
Nemotron 3.5 Bolt E4B 77.9%