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GLM-5.3 vs GPT OSS 20B High

Comparing GLM-5.3 and GPT OSS 20B High across benchmarks, pricing, and capabilities.

Zhipu AI · OpenAI · Updated for 2026

Which is better?

GLM-5.3 and GPT OSS 20B High trade strengths across price, capabilities, and technical limits. The better choice depends on the workload.

On price, GPT OSS 20B High is roughly 10.7x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GLM-5.3 also accepts a larger context window (1,000,000 input tokens), making it the stronger choice for long documents and large codebases.

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

Choose GLM-5.3

  • you process long inputs — it offers a 1,000,000 token context window
  • you want the most recent training data — it shipped Aug 2026

Choose GPT OSS 20B High

  • cost matters — it's about 10.7x cheaper per token
  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

GLM-5.3
Zhipu AI
GPT OSS 20B High
OpenAI
Benchmark wins
—
—
Input price
$1.40 / M
$0.10 / M
Output price
$4.40 / M
$0.50 / M
Context window
1,000,000
131,072
Released
Aug 2026
Aug 2025
License
Unknown
Apache 2.0

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

GLM-5.3 and GPT OSS 20B Highdon'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

GPT OSS 20B High costs less

For input processing, GLM-5.3 ($1.40/1M tokens) is 14.0x more expensive than GPT OSS 20B High ($0.10/1M tokens).

For output processing, GLM-5.3 ($4.40/1M tokens) is 8.8x more expensive than GPT OSS 20B High ($0.50/1M tokens).

In conclusion, GLM-5.3 is more expensive than GPT OSS 20B High.*

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

Lowest available price from all providers
Mon Aug 24 2026 • llm-stats.com
Zhipu AI
GLM-5.3
Input tokens$1.40
Output tokens$4.40
Best providerUnknown Organization
OpenAI
GPT OSS 20B High
Input tokens$0.10
Output tokens$0.50
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Model Size

Parameter count comparison

732.1B diff

GLM-5.3 has 732.1B more parameters than GPT OSS 20B High, making it 3502.9% larger.

Zhipu AI
GLM-5.3
753.0Bparameters
OpenAI
GPT OSS 20B High
20.9Bparameters
753.0B
GLM-5.3
20.9B
GPT OSS 20B High

Context Window

Maximum input and output token capacity

GLM-5.3 accepts 1,000,000 input tokens compared to GPT OSS 20B High's 131,072 tokens. GPT OSS 20B High can generate longer responses up to 131,072 tokens, while GLM-5.3 is limited to 128,000 tokens.

Zhipu AI
GLM-5.3
Input1,000,000 tokens
Output128,000 tokens
OpenAI
GPT OSS 20B High
Input131,072 tokens
Output131,072 tokens
Mon Aug 24 2026 • llm-stats.com

Release Timeline

When each model was launched

GLM-5.3 was released on 2026-08-14, while GPT OSS 20B High was released on 2025-08-05.

GLM-5.3 is 12 months newer than GPT OSS 20B High.

GLM-5.3

Aug 14, 2026

1 weeks ago

1.0yr newer
GPT OSS 20B High

Aug 5, 2025

1.1 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

Provider Availability

GLM-5.3 is available from ZAI. GPT OSS 20B High is available from OpenAI.

GLM-5.3

z logo
Unknown Organization
Input Price:Input: $1.40/1MOutput Price:Output: $4.40/1M

GPT OSS 20B High

openai logo
OpenAI
Input Price:Input: $0.10/1MOutput 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 GLM-5.3 and GPT OSS 20B High side-by-side, then vote on the output you prefer.

GLM-5.3
✓ Preferred
GPT OSS 20B High
Open in Playground

FAQ

Common questions about GLM-5.3 vs GPT OSS 20B High.

Which is better, GLM-5.3 or GPT OSS 20B High?

GLM-5.3 (Zhipu AI) and GPT OSS 20B High (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 OSS 20B High 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 OSS 20B High scores AIME 2025: 98.7%, GPQA: 74.2%.

Is GLM-5.3 cheaper than GPT OSS 20B High?

GPT OSS 20B High is 14.0x cheaper for input tokens. GLM-5.3 costs $1.40/M input and $4.40/M output via z. GPT OSS 20B High costs $0.10/M input and $0.50/M output via openai.

What are the context window sizes for GLM-5.3 and GPT OSS 20B High?

GLM-5.3 supports 1.0M tokens and GPT OSS 20B High supports 131K 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 OSS 20B High?

Key differences include context window (1.0M vs 131K), input pricing ($1.40 vs $0.10/M), licensing (Unknown vs Apache 2.0). See the full comparison above for benchmark-by-benchmark results.

Who makes GLM-5.3 and GPT OSS 20B High?

GLM-5.3 is developed by Zhipu AI and GPT OSS 20B High is developed by OpenAI.

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