GDPval Effort: xHigh 70.9% openai.com for GPT-5.3-Codex (xhigh) on GDPval GDPval (opens in a new tab) Wins or ties Reported February 5, 2026 Launch post OpenAI Self-reported Record for GPT-5.3-Codex on GDPval GDPval OSWorld Verified Effort: xHigh 64.7% openai.com for GPT-5.3-Codex (xhigh) on OSWorld Verified (opens in a new tab) OSWorld-Verified success rate Reported February 5, 2026 Launch post OpenAI Self-reported Record for GPT-5.3-Codex on OSWorld Verified SWE Atlas Codebase QnA — Public; Codex Effort: xHigh Configuration: Codex harness 32.6% labs.scale.com for GPT-5.3-Codex (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-5.3-Codex on SWE Atlas Codebase QnA — Public; Codex SWE Atlas Refactoring — Codex Effort: xHigh Configuration: Codex harness 42.4% labs.scale.com for GPT-5.3-Codex (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-5.3-Codex on SWE Atlas Refactoring — Codex SWE-bench Verified — Epoch AI harness Effort: High Configuration: Epoch AI harness 74.8% epoch.ai for GPT-5.3-Codex (high) on SWE-bench Verified — Epoch AI harness (opens in a new tab) Archived copy (opens in a new tab) Resolved Tasks Reported October 7, 2026 Evaluated February 25, 2026 at 10:37 AM UTC Benchmark leaderboard Epoch AI Independent Record for GPT-5.3-Codex on SWE-bench Verified — Epoch AI harness SWE-bench Verified — Vals AI mini-swe-agent Effort: xHigh Configuration: mini-swe-agent harness 78.0% vals.ai for GPT-5.3-Codex (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-5.3-Codex on SWE-bench Verified — Vals AI mini-swe-agent SWE-bench Pro Public Effort: xHigh 56.8% openai.com for GPT-5.3-Codex (xhigh) on SWE-bench Pro Public (opens in a new tab) Public tasks resolved Reported February 5, 2026 Launch post OpenAI Self-reported Record for GPT-5.3-Codex on SWE-bench Pro Public Terminal-Bench 2.0 Effort: xHigh 77.3% openai.com for GPT-5.3-Codex (xhigh) on Terminal-Bench 2.0 (opens in a new tab) Terminal-Bench Accuracy Reported February 5, 2026 Launch post OpenAI Self-reported Record for GPT-5.3-Codex on Terminal-Bench 2.0 Terminal-Bench 2.0 — Vals AI Terminus 2 Effort: High Configuration: Terminus-2 harness 64.0% vals.ai for GPT-5.3-Codex (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-5.3-Codex on Terminal-Bench 2.0 — Vals AI Terminus 2 Vibe Code Bench 1.1 — OpenHands, October 2026 evaluation Effort: xHigh Configuration: OpenHands harness 61.8% vals.ai for GPT-5.3-Codex (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-5.3-Codex on Vibe Code Bench 1.1 — OpenHands, October 2026 evaluation