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GLM-5.3 vs GPT-5 Codex

Comparing GLM-5.3 and GPT-5 Codex across benchmarks, pricing, and capabilities.

Zhipu AI · OpenAI · Updated for 2026

Which is better?

GLM-5.3 and GPT-5 Codex trade strengths across price, capabilities, and technical limits. The better choice depends on the workload.

Based on current benchmark, pricing, and model metadata for 2026.

Choose GLM-5.3

  • you want the most recent training data — it shipped Aug 2026

Choose GPT-5 Codex

  • you are already invested in the OpenAI ecosystem

At a glance

The differences that matter most.

GLM-5.3
Zhipu AI
GPT-5 Codex
OpenAI
Benchmark wins
—
—
Input price
$1.40 / M
— / M
Output price
$4.40 / M
— / M
Context window
1,000,000
—
Released
Aug 2026
Sep 2025
License
Unknown
Proprietary

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

GLM-5.3 and GPT-5 Codexdon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Arena Performance

Playground indexes and blind preference scores

Context Window

Maximum input and output token capacity

Only GLM-5.3 specifies input context (1,000,000 tokens). Only GLM-5.3 specifies output context (128,000 tokens).

Zhipu AI
GLM-5.3
Input1,000,000 tokens
Output128,000 tokens
OpenAI
GPT-5 Codex
Input- tokens
Output- tokens
Tue Aug 25 2026 • llm-stats.com

Release Timeline

When each model was launched

GLM-5.3 was released on 2026-08-14, while GPT-5 Codex was released on 2025-09-15.

GLM-5.3 is 11 months newer than GPT-5 Codex.

GLM-5.3

Aug 14, 2026

1 weeks ago

11mo newer
GPT-5 Codex

Sep 15, 2025

11 months ago

Knowledge Cutoff

When training data ends

GPT-5 Codex has a documented knowledge cutoff of 2024-09-30, while GLM-5.3's cutoff date is not specified.

We can confirm GPT-5 Codex's training data extends to 2024-09-30, but cannot make a direct comparison without GLM-5.3's cutoff date.

GLM-5.3

—

GPT-5 Codex

Sep 2024

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against GLM-5.3 and GPT-5 Codex side-by-side, then vote on the output you prefer.

GLM-5.3
✓ Preferred
GPT-5 Codex
Open in Playground

FAQ

Common questions about GLM-5.3 vs GPT-5 Codex.

Which is better, GLM-5.3 or GPT-5 Codex?

GLM-5.3 (Zhipu AI) and GPT-5 Codex (OpenAI) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

How does GLM-5.3 compare to GPT-5 Codex in benchmarks?

GLM-5.3 scores Terminal-Bench 2.1: 88.2%, CyberGym: 84.5%, FrontierSWE: 78.1%, Toolathlon: 73.0%, DeepSWE 1.1: 66.9%. GPT-5 Codex scores SWE-Bench Verified: 74.5%.

What are the context window sizes for GLM-5.3 and GPT-5 Codex?

GLM-5.3 supports 1.0M tokens and GPT-5 Codex supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GLM-5.3 and GPT-5 Codex?

Key differences include licensing (Unknown vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes GLM-5.3 and GPT-5 Codex?

GLM-5.3 is developed by Zhipu AI and GPT-5 Codex is developed by OpenAI.

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