FActScore hallucination rate Benchmark Leaderboard | Phaseo

FActScore hallucination rate

Type: percentageHallucinations

Recorded Results

7

Average Score

13.34%

Score Range

2.80% - 38.70%

Leading Model

38.70% - o4 Mini

Scores Over Time

Individual benchmark scores plotted by date.

Models Using This Benchmark

Organisation	Model	Reported	Top Score	Info	Self Reported	Source
OpenAI	o4 Mini	16 Apr 2025	38.70%	High Reasoning Effort	Yes	Source
OpenAI	o3	16 Apr 2025	23.50%	High Reasoning Effort	Yes	Source
OpenAI	GPT 4.1 Mini	14 Apr 2025	10.90%	-	Yes	Source
OpenAI	GPT 5 Nano	07 Aug 2025	7.30%	High Reasoning Effort	Yes	Source
OpenAI	GPT 4.1	14 Apr 2025	6.70%	-	Yes	Source
OpenAI	GPT 5 Mini	07 Aug 2025	3.50%	High Reasoning Effort	Yes	Source
OpenAI	GPT 5	07 Aug 2025	2.80%	High Reasoning Effort	Yes	Source