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GLM-5.3-Flash vs Grok-1.5

Comparing GLM-5.3-Flash and Grok-1.5 across benchmarks, pricing, and capabilities.

Zhipu AI · xAI · Updated for 2026

Which is better?

GLM-5.3-Flash and Grok-1.5 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-Flash

  • you want the most recent training data — it shipped Aug 2026
  • you need open weights you can self-host or fine-tune

Choose Grok-1.5

  • you are already invested in the xAI ecosystem

At a glance

The differences that matter most.

GLM-5.3-Flash
Zhipu AI
Grok-1.5
xAI
Benchmark wins
—
—
Input price
$0.15 / M
— / M
Output price
$0.50 / M
— / M
Context window
1,048,576
—
Released
Aug 2026
Mar 2024
License
MIT
Proprietary

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

GLM-5.3-Flash and Grok-1.5don'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-Flash specifies input context (1,048,576 tokens). Only GLM-5.3-Flash specifies output context (131,072 tokens).

Zhipu AI
GLM-5.3-Flash
Input1,048,576 tokens
Output131,072 tokens
xAI
Grok-1.5
Input- tokens
Output- tokens
Wed Aug 26 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

GLM-5.3-Flash supports multimodal inputs, whereas Grok-1.5 does not.

GLM-5.3-Flash can handle both text and other forms of data like images, making it suitable for multimodal applications.

GLM-5.3-Flash

Text
Images
Audio
Video

Grok-1.5

Text
Images
Audio
Video

License

Usage and distribution terms

GLM-5.3-Flash is licensed under MIT, while Grok-1.5 uses a proprietary license.

License differences may affect how you can use these models in commercial or open-source projects.

GLM-5.3-Flash

MIT

Open weights

Grok-1.5

Proprietary

Closed source

Release Timeline

When each model was launched

GLM-5.3-Flash was released on 2026-08-26, while Grok-1.5 was released on 2024-03-28.

GLM-5.3-Flash is 29 months newer than Grok-1.5.

GLM-5.3-Flash

Aug 26, 2026

0 days ago

2.4yr newer
Grok-1.5

Mar 28, 2024

2.4 years ago

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against GLM-5.3-Flash and Grok-1.5 side-by-side, then vote on the output you prefer.

GLM-5.3-Flash
✓ Preferred
Grok-1.5
Open in Playground

FAQ

Common questions about GLM-5.3-Flash vs Grok-1.5.

Which is better, GLM-5.3-Flash or Grok-1.5?

GLM-5.3-Flash (Zhipu AI) and Grok-1.5 (xAI) 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-Flash compare to Grok-1.5 in benchmarks?

GLM-5.3-Flash scores CharXiv-R: 89.4%, Terminal-Bench 2.1: 84.3%, MMVU: 80.5%, Toolathlon: 78.4%, Chartography: 78.0%. Grok-1.5 scores GSM8k: 90.0%, DocVQA: 85.6%, MMLU: 81.3%, HumanEval: 74.1%, MMMU: 53.6%.

What are the context window sizes for GLM-5.3-Flash and Grok-1.5?

GLM-5.3-Flash supports 1.0M tokens and Grok-1.5 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-Flash and Grok-1.5?

Key differences include multimodal support (yes vs no), licensing (MIT vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes GLM-5.3-Flash and Grok-1.5?

GLM-5.3-Flash is developed by Zhipu AI and Grok-1.5 is developed by xAI.

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