GPT-5.6 Terra
Released 9 Jul 2026$2 input, $12 output per million tokens1.05M contextproprietary
4 results on 4 of 13 boards, latest measured Sep 2026. Compare with other models
Results
Each line sits on its own board's scale. Tall tick: the board leader.
Clinical reasoning and knowledge
- HealthBench Professionallength-adjusted, max reasoning effort (62.4 unadjusted, 3,618 mean response chars); GPT-5.6 system card Table 6, column GPT-5.6-TERRA.0.577Rank 17 of 35Leader GPT-6 Astra (Anthropic run) 0.703
Documentation and coding
- MedScribe (Vals AI)model ID openai/gpt-5.6-terra; max_output_tokens=30000; reasoning_effort=xhigh82.87Rank 47 of 105Leader Claude Opus 5.5 91.43
- MedCode (Vals AI)model ID openai/gpt-5.6-terra; reasoning_effort=xhigh; max_output_tokens=3000043.41Rank 42 of 103Leader Claude Opus 5 63.57
EHR and workflow agents
- 13.3Rank 26 of 43 here, 45 models on the boardLeader erius + claude-opus-5 54.7
Index working
The Clinical Benchmarks Index is this site's own calculation: a weighted average of the board scores times a multiplier for the boards behind it. How it is computed
- HealthBench Professional0.57757.7×0.743length-adjusted, max reasoning effort (62.4 unadjusted, 3,618 mean response chars); GPT-5.6 system card Table 6, column GPT-5.6-TERRA.
- MedScribe (Vals AI)82.8782.9×0.25, near its ceilingNear its ceiling: leader 91.4, weight 0.25model ID openai/gpt-5.6-terra; max_output_tokens=30000; reasoning_effort=xhigh
- MedCode (Vals AI)43.4143.4×0.911model ID openai/gpt-5.6-terra; reasoning_effort=xhigh; max_output_tokens=30000
- Weighted average of 3 boards
- 54.2
- Multiplier for 3 of 10 boards
- × 0.707
- Index
- 54.2 × 0.707 = 38.3
Score: the result on the board’s own 0 to 100 scale. Dot: this model; tick: the board’s leader. Weight: how much the board counts in the weighted average; bold where the board is near its ceiling and counts for less. Each result links to its quote and page; the line under it is the setting it was measured with.
Sources
The quote, page and document for each of the 4 results
17HealthBench Professional length-adjusted 0.577
Printed as 57.7Vendor-reported, measured Jun 2026Configuration: length-adjusted, max reasoning effort (62.4 unadjusted, 3,618 mean response chars); GPT-5.6 system card Table 6, column GPT-5.6-TERRA.GPT-5.6 System Card system card, OpenAI, 9 Jul 2026. Section 5.1 HealthBench, Table 6 (reported as length-adjusted score (unadjusted, mean response length in characters)), column GPT-5.6-TERRAHealthBench Professional length-adjusted 46.2 (51.0, 3616) 39.6 (48.0, 4863) 45.9 (50.0, 3400) 48.1 (51.9, 3308) 51.8 (57.2, 3818) 60.5 (64.1, 3228) 57.7 (62.4, 3618) 55.7 (59.8, 3389)
Every result from this document- Also printed in GPT-5.6 Preview System Card: 57.7, Section 5.1 HealthBench, Table 6 (reported as length-adjusted score (unadjusted, mean response length in characters)) (preview card, published 2026-06-26), column GPT-5.6-TERRA
47MedScribe (Vals AI) gpt-5.6-terra 82.87
Printed as 82.87%Official leaderboard, measured Sep 2026Configuration: model ID openai/gpt-5.6-terra; max_output_tokens=30000; reasoning_effort=xhighVals AI MedScribe leaderboard official leaderboard, Vals AI, 3 Sep 2026. Vals AI MedScribe leaderboard, View: All Models, Task: Overall, row 48 of 105 (GPT-5.6 Terra), Accuracy column; Updated 9/29/2026. Rendered BenchmarkView table; configuration from embedded astro-island BenchmarkView props, benchmarkView.default.tasks.overall["openai/gpt-5.6-terra"].48 | GPT-5.6 Terra | 82.87%±1.95 | $2/$12 | 35.53s
Every result from this document42MedCode (Vals AI) gpt-5.6-terra 43.41
Printed as 43.41%Official leaderboard, measured Sep 2026Configuration: model ID openai/gpt-5.6-terra; reasoning_effort=xhigh; max_output_tokens=30000Vals AI MedCode leaderboard official leaderboard, Vals AI, 29 Sep 2026. MedCode leaderboard, Overall task, All Models expanded, rank 42 of 103; Accuracy column; board Updated 9/29/2026. Rendered table row; configuration from embedded BenchmarkView props benchmarkView.default.tasks.overall["openai/gpt-5.6-terra"].42 | GPT-5.6 Terra | 43.41%±2.17 | $2/$12 | 18.41s
Every result from this document26CHI-Bench All Domains pass@1 13.3
Printed as 13.3%Official leaderboard, measured Jul 2026Configuration: All Domains pass@1; codex harnessCHI-Bench leaderboard (actAVA) official leaderboard, actAVA, 12 Aug 2026. CHI-Bench v1.0.0, All Domains, rank 26, Agent/Model and Accuracy columns; PA/UM/CM follow; board last updated 2026-08-12; board Date column 2026-07-24; accessed 2026-09-30. Linked submission provenance: run 2026-07-22T04:52:42.763467Z to 2026-07-22T06:23:17.742720Z; submitted_at 2026-07-24T23:01:25Z.26 | codex | gpt-5.6-terra | Proprietary | 13.3% | 12.0% | 20.0% | 8.0% | 2026-07-24
Every result from this document- Also printed in CHI-Bench submission manifest: codex + openai/gpt-5.6-terra, submission.model; provenance.started_at / finished_at; results.overall.pass_at_1; retrieved 2026-09-30
Other OpenAI models: GPT-4.1, GPT-4.1 mini, GPT-4o, GPT-5, GPT-5.1, GPT-5.2, GPT-5.3-Codex, GPT-5.4, GPT-5.4 mini, GPT-5.4 nano, GPT-5.5, GPT-5.5 Instant, GPT-5.6 Luna, GPT-5.6 Sol, GPT-5 mini, GPT-5 nano, GPT-6.1 Sol, GPT-6 Astra, GPT-6 Luna, GPT-6 Sol, GPT OSS 120B, GPT OSS 20B, o3, o4-mini