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GLM-5.3 vs Step-3.5-Flash

Comparing GLM-5.3 and Step-3.5-Flash across benchmarks, pricing, and capabilities.

Zhipu AI · StepFun · Updated for 2026

Which is better?

GLM-5.3 and Step-3.5-Flash trade strengths across price, capabilities, and technical limits. The better choice depends on the workload.

On price, Step-3.5-Flash is roughly 12.3x 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 Step-3.5-Flash

  • cost matters — it's about 12.3x 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
Step-3.5-Flash
StepFun
Benchmark wins
—
—
Input price
$1.40 / M
$0.10 / M
Output price
$4.40 / M
$0.40 / M
Context window
1,000,000
65,536
Released
Aug 2026
Feb 2026
License
Unknown
Apache 2.0

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

GLM-5.3 and Step-3.5-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

Step-3.5-Flash costs less

For input processing, GLM-5.3 ($1.40/1M tokens) is 14.0x more expensive than Step-3.5-Flash ($0.10/1M tokens).

For output processing, GLM-5.3 ($4.40/1M tokens) is 11.0x more expensive than Step-3.5-Flash ($0.40/1M tokens).

In conclusion, GLM-5.3 is more expensive than Step-3.5-Flash.*

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

Lowest available price from all providers
Tue Aug 25 2026 • llm-stats.com
Zhipu AI
GLM-5.3
Input tokens$1.40
Output tokens$4.40
Best providerUnknown Organization
StepFun
Step-3.5-Flash
Input tokens$0.10
Output tokens$0.40
Best providerStepFun
Notice missing or incorrect data?Start an Issue→

Model Size

Parameter count comparison

557.0B diff

GLM-5.3 has 557.0B more parameters than Step-3.5-Flash, making it 284.2% larger.

Zhipu AI
GLM-5.3
753.0Bparameters
StepFun
Step-3.5-Flash
196.0Bparameters
753.0B
GLM-5.3
196.0B
Step-3.5-Flash

Context Window

Maximum input and output token capacity

GLM-5.3 accepts 1,000,000 input tokens compared to Step-3.5-Flash's 65,536 tokens. GLM-5.3 can generate longer responses up to 128,000 tokens, while Step-3.5-Flash is limited to 8,192 tokens.

Zhipu AI
GLM-5.3
Input1,000,000 tokens
Output128,000 tokens
StepFun
Step-3.5-Flash
Input65,536 tokens
Output8,192 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 Step-3.5-Flash was released on 2026-02-02.

GLM-5.3 is 6 months newer than Step-3.5-Flash.

GLM-5.3

Aug 14, 2026

1 weeks ago

6mo newer
Step-3.5-Flash

Feb 2, 2026

6 months 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. Step-3.5-Flash is available from StepFun.

GLM-5.3

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

Step-3.5-Flash

stepfun logo
StepFun
Input Price:Input: $0.10/1MOutput Price:Output: $0.40/1M
* 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 Step-3.5-Flash side-by-side, then vote on the output you prefer.

GLM-5.3
✓ Preferred
Step-3.5-Flash
Open in Playground

FAQ

Common questions about GLM-5.3 vs Step-3.5-Flash.

Which is better, GLM-5.3 or Step-3.5-Flash?

GLM-5.3 (Zhipu AI) and Step-3.5-Flash (StepFun) 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 Step-3.5-Flash 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%. Step-3.5-Flash scores AIME 2025: 97.3%, Tau-bench: 88.2%, LiveCodeBench v6: 86.4%, IMO-AnswerBench: 85.4%, SWE-Bench Verified: 74.4%.

Is GLM-5.3 cheaper than Step-3.5-Flash?

Step-3.5-Flash is 14.0x cheaper for input tokens. GLM-5.3 costs $1.40/M input and $4.40/M output via z. Step-3.5-Flash costs $0.10/M input and $0.40/M output via stepfun.

What are the context window sizes for GLM-5.3 and Step-3.5-Flash?

GLM-5.3 supports 1.0M tokens and Step-3.5-Flash supports 66K 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 Step-3.5-Flash?

Key differences include context window (1.0M vs 66K), 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 Step-3.5-Flash?

GLM-5.3 is developed by Zhipu AI and Step-3.5-Flash is developed by StepFun.

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