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Gemini 1.5 Pro vs GLM-5.3-Flash

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

Google · Zhipu AI · Updated for 2026

Which is better?

Gemini 1.5 Pro and GLM-5.3-Flash trade strengths across price, capabilities, and technical limits. The better choice depends on the workload.

On price, GLM-5.3-Flash is roughly 18.4x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Gemini 1.5 Pro also accepts a larger context window (2,097,152 input tokens), making it the stronger choice for long documents and large codebases.

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

Choose Gemini 1.5 Pro

  • you process long inputs — it offers a 2,097,152 token context window

Choose GLM-5.3-Flash

  • cost matters — it's about 18.4x cheaper per token
  • you want the most recent training data — it shipped Aug 2026
  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Gemini 1.5 Pro
Google
GLM-5.3-Flash
Zhipu AI
Benchmark wins
—
—
Input price
$2.50 / M
$0.15 / M
Output price
$10.00 / M
$0.50 / M
Context window
2,097,152
1,000,000
Released
May 2024
Aug 2026
License
Proprietary
MIT

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

Gemini 1.5 Pro and GLM-5.3-Flashdon'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

Pricing Analysis

Price comparison per million tokens

GLM-5.3-Flash costs less

For input processing, Gemini 1.5 Pro ($2.50/1M tokens) is 16.7x more expensive than GLM-5.3-Flash ($0.15/1M tokens).

For output processing, Gemini 1.5 Pro ($10.00/1M tokens) is 20.0x more expensive than GLM-5.3-Flash ($0.50/1M tokens).

In conclusion, Gemini 1.5 Pro is more expensive than GLM-5.3-Flash.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Wed Aug 26 2026 • llm-stats.com
Google
Gemini 1.5 Pro
Input tokens$2.50
Output tokens$10.00
Best providerGoogle
Zhipu AI
GLM-5.3-Flash
Input tokens$0.15
Output tokens$0.50
Best providerUnknown Organization
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Gemini 1.5 Pro accepts 2,097,152 input tokens compared to GLM-5.3-Flash's 1,000,000 tokens. GLM-5.3-Flash can generate longer responses up to 131,072 tokens, while Gemini 1.5 Pro is limited to 8,192 tokens.

Google
Gemini 1.5 Pro
Input2,097,152 tokens
Output8,192 tokens
Zhipu AI
GLM-5.3-Flash
Input1,000,000 tokens
Output131,072 tokens
Wed Aug 26 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Gemini 1.5 Pro and GLM-5.3-Flash support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Gemini 1.5 Pro

Text
Images
Audio
Video

GLM-5.3-Flash

Text
Images
Audio
Video

License

Usage and distribution terms

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

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

Gemini 1.5 Pro

Proprietary

Closed source

GLM-5.3-Flash

MIT

Open weights

Release Timeline

When each model was launched

Gemini 1.5 Pro was released on 2024-05-01, while GLM-5.3-Flash was released on 2026-08-26.

GLM-5.3-Flash is 28 months newer than Gemini 1.5 Pro.

Gemini 1.5 Pro

May 1, 2024

2.3 years ago

GLM-5.3-Flash

Aug 26, 2026

0 days ago

2.3yr newer

Knowledge Cutoff

When training data ends

Gemini 1.5 Pro has a documented knowledge cutoff of 2023-11-01, while GLM-5.3-Flash's cutoff date is not specified.

We can confirm Gemini 1.5 Pro's training data extends to 2023-11-01, but cannot make a direct comparison without GLM-5.3-Flash's cutoff date.

Gemini 1.5 Pro

Nov 2023

GLM-5.3-Flash

—

Provider Availability

Gemini 1.5 Pro is available from Google. GLM-5.3-Flash is available from ZAI.

Gemini 1.5 Pro

google logo
Google
Input Price:Input: $2.50/1MOutput Price:Output: $10.00/1M

GLM-5.3-Flash

z logo
Unknown Organization
Input Price:Input: $0.15/1MOutput Price:Output: $0.50/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

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

Gemini 1.5 Pro
✓ Preferred
GLM-5.3-Flash
Open in Playground

FAQ

Common questions about Gemini 1.5 Pro vs GLM-5.3-Flash.

Which is better, Gemini 1.5 Pro or GLM-5.3-Flash?

Gemini 1.5 Pro (Google) and GLM-5.3-Flash (Zhipu AI) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

How does Gemini 1.5 Pro compare to GLM-5.3-Flash in benchmarks?

Gemini 1.5 Pro scores XSTest: 98.8%, FLEURS: 93.3%, HellaSwag: 93.3%, GSM8k: 90.8%, BIG-Bench Hard: 89.2%. GLM-5.3-Flash scores CharXiv-R: 89.4%, Terminal-Bench 2.1: 84.3%, MMVU: 80.5%, Toolathlon: 78.4%, MVBench: 77.8%.

Is Gemini 1.5 Pro cheaper than GLM-5.3-Flash?

GLM-5.3-Flash is 16.7x cheaper for input tokens. Gemini 1.5 Pro costs $2.50/M input and $10.00/M output via google. GLM-5.3-Flash costs $0.15/M input and $0.50/M output via z.

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

Gemini 1.5 Pro supports 2.1M tokens and GLM-5.3-Flash supports 1.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Gemini 1.5 Pro and GLM-5.3-Flash?

Key differences include context window (2.1M vs 1.0M), input pricing ($2.50 vs $0.15/M), licensing (Proprietary vs MIT). See the full comparison above for benchmark-by-benchmark results.

Who makes Gemini 1.5 Pro and GLM-5.3-Flash?

Gemini 1.5 Pro is developed by Google and GLM-5.3-Flash is developed by Zhipu AI.

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