GPT 5.5

Release Date: Apr 23, 2026

Developer OpenAIΒ πŸ‡ΊπŸ‡Έ
Context Window 1M
Max Output Tokens 128k
Token Costs (in/out) $5.00/30.00
Weights Private
Input Modalities

Accuracy

57.41 % Β± 1.15

Cost / Test (Vals Index)

$ 6.142

Latency

20 min 51 s

Vals Index
BenchmarksAccuracyRankings

0.0%

Β±1.15
10/46

0.0%

Β±4.16
5/49

0.0%

Β±5.16
3/22

0.0%

Β±2.87
11/46

0.0%

Β±0.55
15/49

0.0%

Β±3.41
12/49

0.0%

Β±2.19
19/85

0.0%

Β±1.93
9/84

0.0%

Β±0.91
9/95

0.0%

Β±3.95
10/76

0.0%

Β±1.19
3/5

0.0%

Β±0.85
23/140

0.0%

Β±4.54
16/84

0.0%

Β±1.29
9/133

0.0%

Β±1.02
33/138

0.0%

Β±0.41
9/137

0.0%

Β±0.32
19/133

0.0%

Β±0.77
7/89

0.0%

Β±0.50
6/39

0.0%

Β±4.52
4/28

0.0%

Β±1.70
15/83

0.0%

Β±0.65
8/54
Proprietary BenchmarksAcademic BenchmarksIndustry Partners
Vals
Default Provider : OpenAI
Temperature: Default
Top P: Default
Top K: Default
Max Output Tokens: 128,000
Reasoning Effort: xhigh

Updates

Apr 23, 2026

OpenAI released GPT 5.5, and it lands near the top of multiple Vals leaderboards, taking #2 on the overall Vals Index with a meaningful jump over GPT 5.4 (xhigh) in roughly six weeks.