APEX-Agents Original Effort: xHigh 55.1% mercor.com for GPT-5.5 (xhigh) on APEX-Agents Original (opens in a new tab) Archived copy (opens in a new tab) Pass rate Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for GPT-5.5 on APEX-Agents Original AutomationBench 1.0.6 Effort: Low 2.6% zapier.com for GPT-5.5 (low) on AutomationBench 1.0.6 (opens in a new tab) Archived copy (opens in a new tab) Task pass rate Reported October 7, 2026 Benchmark leaderboard Zapier Independent Zapier AutomationBench Team Record for GPT-5.5 on AutomationBench 1.0.6 AutomationBench 1.0.6 Effort: Medium 9.0% zapier.com for GPT-5.5 (medium) on AutomationBench 1.0.6 (opens in a new tab) Archived copy (opens in a new tab) Task pass rate Reported October 7, 2026 Benchmark leaderboard Zapier Independent Zapier AutomationBench Team Record for GPT-5.5 on AutomationBench 1.0.6 AutomationBench 1.0.6 Effort: High 12.8% zapier.com for GPT-5.5 (high) on AutomationBench 1.0.6 (opens in a new tab) Archived copy (opens in a new tab) Task pass rate Reported October 7, 2026 Benchmark leaderboard Zapier Independent Zapier AutomationBench Team Record for GPT-5.5 on AutomationBench 1.0.6 AutomationBench 1.0.6 Effort: xHigh 16.6% zapier.com for GPT-5.5 (xhigh) on AutomationBench 1.0.6 (opens in a new tab) Archived copy (opens in a new tab) Task pass rate Reported October 7, 2026 Benchmark leaderboard Zapier Independent Zapier AutomationBench Team Record for GPT-5.5 on AutomationBench 1.0.6 AutomationBench 1.0.6 1.1% zapier.com for GPT-5.5 on AutomationBench 1.0.6 (opens in a new tab) Archived copy (opens in a new tab) Task pass rate Reported October 7, 2026 Benchmark leaderboard Zapier Independent Zapier AutomationBench Team Record for GPT-5.5 on AutomationBench 1.0.6 BrowseComp 130-question subset — Mercor web research agent Effort: xHigh Configuration: Mercor web research agent, 100 steps, 3 hours 77.7% mercor.com for GPT-5.5 (xhigh) on BrowseComp 130-question subset — Mercor web research agent (opens in a new tab) Archived copy (opens in a new tab) BrowseComp Accuracy Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for GPT-5.5 on BrowseComp 130-question subset — Mercor web research agent BrowseComp Effort: xHigh 84.4% openai.com for GPT-5.5 (xhigh) on BrowseComp BrowseComp (opens in a new tab) BrowseComp Accuracy Reported April 23, 2026 Launch post OpenAI Self-reported Record for GPT-5.5 on BrowseComp BrowseComp Chartography October 2026 leaderboard Effort: xHigh 31.0% surgehq.ai for GPT-5.5 (xHigh) on Chartography October 2026 leaderboard (opens in a new tab) Archived copy (opens in a new tab) Chartography Pass@1 Reported October 7, 2026 Benchmark leaderboard Surge AI Independent Record for GPT-5.5 on Chartography October 2026 leaderboard CharXiv Descriptive and reasoning — Mercor single-shot Effort: xHigh Configuration: Mercor single-shot agent 94.6% mercor.com for GPT-5.5 (xhigh) on CharXiv Descriptive and reasoning — Mercor single-shot (opens in a new tab) Archived copy (opens in a new tab) CharXiv Accuracy Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for GPT-5.5 on CharXiv Descriptive and reasoning — Mercor single-shot DeepSWE 1.1 Effort: xHigh 67.0% deepswe.datacurve.ai for GPT-5.5 (xhigh) on DeepSWE 1.1 (opens in a new tab) Archived copy (opens in a new tab) DeepSWE Pass@1 Reported September 22, 2026 Benchmark leaderboard Datacurve Independent Record for GPT-5.5 on DeepSWE 1.1 DeepSWE 1.1 — Mercor mini-swe-agent, 500 steps Effort: xHigh Configuration: Mercor mini-swe-agent, 500 steps, 2 hours 66.1% mercor.com for GPT-5.5 (xhigh) on DeepSWE 1.1 — Mercor mini-swe-agent, 500 steps (opens in a new tab) Archived copy (opens in a new tab) DeepSWE Pass@1 Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for GPT-5.5 on DeepSWE 1.1 — Mercor mini-swe-agent, 500 steps Finance Agent Benchmark 2 — October 2026 evaluation Effort: xHigh 51.8% vals.ai for GPT-5.5 (xhigh) on Finance Agent Benchmark 2 — October 2026 evaluation (opens in a new tab) Archived copy (opens in a new tab) Finance Agent Accuracy Reported October 6, 2026 Benchmark leaderboard Vals AI Independent Record for GPT-5.5 on Finance Agent Benchmark 2 — October 2026 evaluation GDPval Effort: xHigh 84.9% openai.com for GPT-5.5 (xhigh) on GDPval GDPval (opens in a new tab) Wins or ties Reported April 23, 2026 Launch post OpenAI Self-reported Record for GPT-5.5 on GDPval GDPval GPQA Diamond Effort: xHigh 93.6% openai.com for GPT-5.5 (xhigh) on Graduate-Level Google-Proof Q&A Diamond (opens in a new tab) GPQA Diamond Accuracy Reported April 23, 2026 Launch post OpenAI Self-reported Record for GPT-5.5 on Graduate-Level Google-Proof Q&A Diamond GPQA Diamond — Epoch AI harness Effort: None Configuration: Epoch AI harness 77.3% epoch.ai for GPT-5.5 (none) on Graduate-Level Google-Proof Q&A Diamond — Epoch AI harness (opens in a new tab) Archived copy (opens in a new tab) GPQA Diamond Accuracy Reported October 7, 2026 Evaluated August 7, 2026 at 12:57 AM UTC Benchmark leaderboard Epoch AI Independent Record for GPT-5.5 on Graduate-Level Google-Proof Q&A Diamond — Epoch AI harness GPQA Diamond — Epoch AI harness Effort: Low Configuration: Epoch AI harness 90.7% epoch.ai for GPT-5.5 (low) on Graduate-Level Google-Proof Q&A Diamond — Epoch AI harness (opens in a new tab) Archived copy (opens in a new tab) GPQA Diamond Accuracy Reported October 7, 2026 Evaluated May 5, 2026 at 6:00 PM UTC Benchmark leaderboard Epoch AI Independent Record for GPT-5.5 on Graduate-Level Google-Proof Q&A Diamond — Epoch AI harness GPQA Diamond — Mercor single-shot Effort: xHigh Configuration: Mercor single-shot agent 94.6% mercor.com for GPT-5.5 (xhigh) on Graduate-Level Google-Proof Q&A Diamond — Mercor single-shot (opens in a new tab) Archived copy (opens in a new tab) GPQA Diamond Accuracy Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for GPT-5.5 on Graduate-Level Google-Proof Q&A Diamond — Mercor single-shot GPQA Diamond — Vals AI harness Effort: xHigh Configuration: Vals AI harness: mean of zero-shot and few-shot CoT 93.2% vals.ai for GPT-5.5 (xhigh) on Graduate-Level Google-Proof Q&A Diamond — Vals AI harness (opens in a new tab) Archived copy (opens in a new tab) GPQA Diamond Accuracy Reported September 1, 2026 Benchmark leaderboard Vals AI Independent Record for GPT-5.5 on Graduate-Level Google-Proof Q&A Diamond — Vals AI harness HLAB October 2026 evaluation Effort: xHigh 3.8% vals.ai for GPT-5.5 (xhigh) on Harvey's Legal Agent Benchmark October 2026 evaluation (opens in a new tab) Archived copy (opens in a new tab) HLAB Task Pass Rate Reported October 6, 2026 Benchmark leaderboard Vals AI Independent Record for GPT-5.5 on Harvey's Legal Agent Benchmark October 2026 evaluation Humanity's Last Exam Full set — No tools Effort: xHigh Configuration: No tools 41.4% openai.com for GPT-5.5 (xhigh) on Humanity's Last Exam Full set — No tools (opens in a new tab) Humanity's Last Exam Accuracy Reported April 23, 2026 Launch post OpenAI Self-reported Record for GPT-5.5 on Humanity's Last Exam Full set — No tools Humanity's Last Exam Full set — With tools Effort: xHigh Configuration: With tools 52.2% openai.com for GPT-5.5 (xhigh) on Humanity's Last Exam Full set — With tools (opens in a new tab) Humanity's Last Exam Accuracy Reported April 23, 2026 Launch post OpenAI Self-reported Record for GPT-5.5 on Humanity's Last Exam Full set — With tools Humanity's Last Exam Text only — Mercor single-shot Effort: xHigh Configuration: Mercor single-shot agent 46.5% mercor.com for GPT-5.5 (xhigh) on Humanity's Last Exam Text only — Mercor single-shot (opens in a new tab) Archived copy (opens in a new tab) Humanity's Last Exam Accuracy Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for GPT-5.5 on Humanity's Last Exam Text only — Mercor single-shot MCP Atlas Public, April 2026 update Effort: xHigh 75.3% labs.scale.com for GPT-5.5 (xhigh) on MCP Atlas Public, April 2026 update (opens in a new tab) Pass rate Reported September 24, 2026 Benchmark leaderboard Scale AI Independent Record for GPT-5.5 on MCP Atlas Public, April 2026 update MedXpertQA MM — Mercor single-shot Effort: xHigh Configuration: Mercor single-shot agent 76.7% mercor.com for GPT-5.5 (xhigh) on MedXpertQA MM — Mercor single-shot (opens in a new tab) Archived copy (opens in a new tab) Accuracy Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for GPT-5.5 on MedXpertQA MM — Mercor single-shot MMLU-Pro Original — Mercor single-shot Effort: xHigh Configuration: Mercor single-shot agent 88.9% mercor.com for GPT-5.5 (xhigh) on MMLU-Pro Original — Mercor single-shot (opens in a new tab) Archived copy (opens in a new tab) Accuracy Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for GPT-5.5 on MMLU-Pro Original — Mercor single-shot MMLU-Pro Original — Vals AI harness Effort: xHigh Configuration: Vals AI harness 88.1% vals.ai for GPT-5.5 (xhigh) on MMLU-Pro Original — Vals AI harness (opens in a new tab) Archived copy (opens in a new tab) Accuracy Reported September 1, 2026 Benchmark leaderboard Vals AI Independent Record for GPT-5.5 on MMLU-Pro Original — Vals AI harness MMMU-Pro 1,730 questions — Mercor single-shot Effort: xHigh Configuration: Mercor single-shot agent 81.8% mercor.com for GPT-5.5 (xhigh) on MMMU-Pro 1,730 questions — Mercor single-shot (opens in a new tab) Archived copy (opens in a new tab) MMMU-Pro accuracy Setting: Not stated Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for GPT-5.5 on MMMU-Pro 1,730 questions — Mercor single-shot MMMU-Pro No tools Effort: xHigh Configuration: No tools 81.2% openai.com for GPT-5.5 (xhigh) on MMMU-Pro No tools (opens in a new tab) MMMU-Pro accuracy Setting: Not stated Reported April 23, 2026 Launch post OpenAI Self-reported Record for GPT-5.5 on MMMU-Pro No tools MMMU-Pro Vals AI harness Effort: xHigh Configuration: Vals AI harness 88.3% vals.ai for GPT-5.5 (xhigh) on MMMU-Pro Vals AI harness (opens in a new tab) Archived copy (opens in a new tab) MMMU-Pro accuracy Setting: Standard (4 options) Reported September 1, 2026 Benchmark leaderboard Vals AI Independent Record for GPT-5.5 on MMMU-Pro Vals AI harness MMMU-Pro With tools Effort: xHigh Configuration: With tools 83.2% openai.com for GPT-5.5 (xhigh) on MMMU-Pro With tools (opens in a new tab) MMMU-Pro accuracy Setting: Not stated Reported April 23, 2026 Launch post OpenAI Self-reported Record for GPT-5.5 on MMMU-Pro With tools OSWorld Verified Effort: xHigh 78.7% openai.com for GPT-5.5 (xhigh) on OSWorld Verified (opens in a new tab) OSWorld-Verified success rate Reported April 23, 2026 Launch post OpenAI Self-reported Record for GPT-5.5 on OSWorld Verified PostTrainBench 1.1 — Codex CLI Effort: xHigh Configuration: Codex harness 27.2% posttrainbench.com for GPT-5.5 (xHigh) on PostTrainBench 1.1 — Codex CLI (opens in a new tab) Archived copy (opens in a new tab) PostTrainBench Weighted Aggregate Reported October 6, 2026 Benchmark leaderboard PostTrainBench Independent PostTrainBench Team Record for GPT-5.5 on PostTrainBench 1.1 — Codex CLI PostTrainBench 1.2 — Codex CLI Effort: xHigh Configuration: Codex harness 23.9% posttrainbench.com for GPT-5.5 (xHigh) on PostTrainBench 1.2 — Codex CLI (opens in a new tab) Archived copy (opens in a new tab) PostTrainBench Weighted Aggregate Reported October 6, 2026 Benchmark leaderboard PostTrainBench Independent PostTrainBench Team Record for GPT-5.5 on PostTrainBench 1.2 — Codex CLI Riemann-bench October 2026 leaderboard Effort: xHigh 55.2% surgehq.ai for GPT-5.5 (xHigh) on Riemann-bench October 2026 leaderboard (opens in a new tab) Archived copy (opens in a new tab) Riemann-bench Pass@1 Reported October 7, 2026 Benchmark leaderboard Surge AI Independent Record for GPT-5.5 on Riemann-bench October 2026 leaderboard SimpleQA Verified Original — Epoch AI harness Effort: xHigh Configuration: Epoch AI harness 63.0% epoch.ai for GPT-5.5 (xhigh) on SimpleQA Verified Original — Epoch AI harness (opens in a new tab) Archived copy (opens in a new tab) Accuracy Reported October 7, 2026 Evaluated August 27, 2026 at 7:28 PM UTC Benchmark leaderboard Epoch AI Independent Record for GPT-5.5 on SimpleQA Verified Original — Epoch AI harness SWE Atlas Codebase QnA — Mercor mini-swe-agent, 250 steps Effort: xHigh Configuration: Mercor mini-swe-agent, 250 steps, 1 hour 45.2% mercor.com for GPT-5.5 (xhigh) on SWE Atlas Codebase QnA — Mercor mini-swe-agent, 250 steps (opens in a new tab) Archived copy (opens in a new tab) Mean pass@1 Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for GPT-5.5 on SWE Atlas Codebase QnA — Mercor mini-swe-agent, 250 steps SWE Atlas Codebase QnA — Public; Codex Effort: xHigh Configuration: Codex harness 45.4% labs.scale.com for GPT-5.5 (xHigh) on SWE Atlas Codebase QnA — Public; Codex (opens in a new tab) Archived copy (opens in a new tab) Mean pass@1 Reported October 7, 2026 Benchmark leaderboard Scale AI Independent Record for GPT-5.5 on SWE Atlas Codebase QnA — Public; Codex SWE Atlas Refactoring — Codex Effort: xHigh Configuration: Codex harness 44.8% labs.scale.com for GPT-5.5 (xHigh) on SWE Atlas Refactoring — Codex (opens in a new tab) Archived copy (opens in a new tab) Mean pass@1 Reported October 7, 2026 Benchmark leaderboard Scale AI Independent Record for GPT-5.5 on SWE Atlas Refactoring — Codex SWE-bench Multilingual — Mercor mini-swe-agent, 1000 steps Effort: xHigh Configuration: Mercor mini-swe-agent, 1000 steps, 3 hours 77.7% mercor.com for GPT-5.5 (xhigh) on SWE-bench Multilingual — Mercor mini-swe-agent, 1000 steps (opens in a new tab) Archived copy (opens in a new tab) Resolved Tasks Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for GPT-5.5 on SWE-bench Multilingual — Mercor mini-swe-agent, 1000 steps SWE-bench Verified — Mercor mini-swe-agent, 1000 steps Effort: xHigh Configuration: Mercor mini-swe-agent, 1000 steps, 3 hours 78.8% mercor.com for GPT-5.5 (xhigh) on SWE-bench Verified — Mercor mini-swe-agent, 1000 steps (opens in a new tab) Archived copy (opens in a new tab) Resolved Tasks Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for GPT-5.5 on SWE-bench Verified — Mercor mini-swe-agent, 1000 steps SWE-bench Verified — Vals AI mini-swe-agent Effort: xHigh Configuration: mini-swe-agent harness 82.6% vals.ai for GPT-5.5 (xhigh) on SWE-bench Verified — Vals AI mini-swe-agent (opens in a new tab) Archived copy (opens in a new tab) Resolved Tasks Reported September 1, 2026 Benchmark leaderboard Vals AI Independent Record for GPT-5.5 on SWE-bench Verified — Vals AI mini-swe-agent Terminal-Bench 2.0 Effort: xHigh 82.7% openai.com for GPT-5.5 (xhigh) on Terminal-Bench 2.0 (opens in a new tab) Terminal-Bench Accuracy Reported April 23, 2026 Launch post OpenAI Self-reported Record for GPT-5.5 on Terminal-Bench 2.0 Terminal-Bench 2.0 — Vals AI Terminus 2 Effort: High Configuration: Terminus-2 harness 73.2% vals.ai for GPT-5.5 (high) on Terminal-Bench 2.0 — Vals AI Terminus 2 (opens in a new tab) Archived copy (opens in a new tab) Terminal-Bench Accuracy Reported June 4, 2026 Benchmark leaderboard Vals AI Independent Record for GPT-5.5 on Terminal-Bench 2.0 — Vals AI Terminus 2 Terminal-Bench 2.1 — Mercor Terminus 2 Effort: xHigh Configuration: Mercor Terminus 2, 1000 steps, 3 hours 83.1% mercor.com for GPT-5.5 (xhigh) on Terminal-Bench 2.1 — Mercor Terminus 2 (opens in a new tab) Archived copy (opens in a new tab) Terminal-Bench Accuracy Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for GPT-5.5 on Terminal-Bench 2.1 — Mercor Terminus 2 Terminal-Bench 2.1 — Vals AI Terminus 2 Effort: High Configuration: Terminus-2 harness 76.4% vals.ai for GPT-5.5 (high) on Terminal-Bench 2.1 — Vals AI Terminus 2 (opens in a new tab) Archived copy (opens in a new tab) Terminal-Bench Accuracy Reported September 28, 2026 Benchmark leaderboard Vals AI Independent Record for GPT-5.5 on Terminal-Bench 2.1 — Vals AI Terminus 2 Toolathlon Verified Effort: xHigh 73.5% toolathlon.xyz for GPT-5.5 (xhigh) on Toolathlon Verified (opens in a new tab) Archived copy (opens in a new tab) Tasks completed Reported June 30, 2026 Benchmark leaderboard Toolathlon Independent Toolathlon Authors Record for GPT-5.5 on Toolathlon Verified Vibe Code Bench 1.1 — Codex, October 2026 evaluation Configuration: Codex harness 58.2% vals.ai for GPT-5.5 on Vibe Code Bench 1.1 — Codex, October 2026 evaluation (opens in a new tab) Archived copy (opens in a new tab) Vibe Code Bench Score Reported October 6, 2026 Benchmark leaderboard Vals AI Independent Record for GPT-5.5 on Vibe Code Bench 1.1 — Codex, October 2026 evaluation Vibe Code Bench 1.1 — Factory, October 2026 evaluation Configuration: Factory harness 67.4% vals.ai for GPT-5.5 on Vibe Code Bench 1.1 — Factory, October 2026 evaluation (opens in a new tab) Archived copy (opens in a new tab) Vibe Code Bench Score Reported October 6, 2026 Benchmark leaderboard Vals AI Independent Record for GPT-5.5 on Vibe Code Bench 1.1 — Factory, October 2026 evaluation Vibe Code Bench 1.1 — OpenHands, October 2026 evaluation Effort: xHigh Configuration: OpenHands harness 69.8% vals.ai for GPT-5.5 (xhigh) on Vibe Code Bench 1.1 — OpenHands, October 2026 evaluation (opens in a new tab) Archived copy (opens in a new tab) Vibe Code Bench Score Reported October 6, 2026 Benchmark leaderboard Vals AI Independent Record for GPT-5.5 on Vibe Code Bench 1.1 — OpenHands, October 2026 evaluation