Independent AI evaluation platform Artificial Analysis has published its benchmark results for Z.ai's GLM-5.3, awarding the reasoning model a score of 60 on its Intelligence Index v4.1.1. The result places GLM-5.3 level with Moonshot AI's Kimi K3 and three points behind frontier leader Claude Opus 5 (63).
The evaluation tested GLM-5.3 at its maximum reasoning effort configuration across a nine-part battery that measures agentic tool execution, terminal coding, graduate-level scientific problem-solving, physics, factual reliability, and long-context comprehension. Across a comparison class of 181 models with a median score of 35, GLM-5.3 ranks eighth overall.
Post-Training Gains on Base Weights
Z.ai released GLM-5.3 on August 14, 2026, without initiating a new base pretraining run. The 753-billion parameter model uses the identical base weights as its predecessor, GLM-5.2. All measured performance improvements stem from scaled reinforcement learning applied across long-horizon task environments over a four-week post-training cycle.
Vendor-reported data highlighted significant jumps on specialized coding benchmarks, with Terminal-Bench 3.0 climbing from 4.6 to 28.3 and DeepSWE v1.1 rising from 46.2 to 66.9. Artificial Analysis's independent test run confirms that these post-training gains translate into broader general reasoning and tool-use capabilities under standardized third-party evaluation.
Inference Cost and Token Economics
While GLM-5.3 matches Kimi K3's score of 60, the two models differ significantly in API pricing and token consumption patterns:
- Token Pricing: Z.ai lists GLM-5.3 at $1.40 per million input tokens and $4.40 per million output tokens. In comparison, Moonshot prices Kimi K3 at $3.00 per million input and $15.00 per million output tokens.
- Cost Per Evaluation Task: Across the Intelligence Index benchmark, GLM-5.3 averaged $0.68 per task, compared to $0.84 for Kimi K3 and $2.34 for Claude Opus 5. The full evaluation run across the suite cost $1,238.50 on Z.ai's API.
- Generation Verbosity: GLM-5.3 exhibited high output token volume during reasoning steps, generating 170 million output tokens across the entire evaluation battery against a class median of 72 million tokens.
Deployment and Planned Open Weights
GLM-5.3 is currently accessible through Z.ai's hosted API and GLM Coding Plan subscriptions. The model enforces active reasoning traces and supports three selectable effort tiers, rejecting API calls that attempt to disable reasoning mode.
Z.ai has scheduled an open-weights release two weeks after launch following final safety evaluations, which would establish GLM-5.3 alongside Kimi K3 as the highest-scoring open-weight architectures on the Artificial Analysis leaderboard.
