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Gemini 3.5 Flash vs Solar Pro 4

Gemini 3.5 Flash leads the LLM Stats Score 43.6 to 36.0. Solar Pro 4 is 6.4x cheaper per token.

Google · Upstage · Updated for 2026

Which is better?

Gemini 3.5 Flash leads the overall LLM Stats Score 43.6 to 36.0, ranking #34 overall.

On price, Solar Pro 4 is roughly 6.4x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Gemini 3.5 Flash also accepts a larger context window (1,048,576 input tokens), making it the stronger choice for long documents and large codebases.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Gemini 3.5 Flash

  • overall performance matters — it scores 43.6 and ranks #34 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you process long inputs — it offers a 1,048,576 token context window

Choose Solar Pro 4

  • cost matters — it's about 6.4x cheaper per token
  • you want the most recent training data — it shipped Aug 2026

At a glance

The differences that matter most.

Gemini 3.5 Flash
Google
Solar Pro 4
Upstage
Core performance indexes
LLM Stats Score
43.6
#34
36.0
#72
Reasoning
44.4
#31
35.6
#71
Coding
33.8
#32
22.1
#73
Agents
31.5
#26
13.8
#84
Cost, coverage & limits
Benchmark wins
—
—
Input price
$1.50 / M
$0.30 / M
Output price
$9.00 / M
$1.20 / M
Context window
1,048,576
524,288

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
Gemini 3.5 Flash
Solar Pro 4
Math
30.7#67
32.0#55
Tool use
31.5#10
15.3#81
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

16 reported for Gemini 3.5 Flash · 9 for Solar Pro 4

No common benchmarks found

Gemini 3.5 Flash and Solar Pro 4don't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Solar Pro 4 costs less

For input processing, Gemini 3.5 Flash ($1.50/1M tokens) is 5.0x more expensive than Solar Pro 4 ($0.30/1M tokens).

For output processing, Gemini 3.5 Flash ($9.00/1M tokens) is 7.5x more expensive than Solar Pro 4 ($1.20/1M tokens).

In conclusion, Gemini 3.5 Flash is more expensive than Solar Pro 4.*

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

Lowest available price from all providers
Fri Aug 28 2026 • llm-stats.com
Google
Gemini 3.5 Flash
Input tokens$1.50
Output tokens$9.00
Best providerGoogle
Upstage
Solar Pro 4
Input tokens$0.30
Output tokens$1.20
Best providerUnknown Organization
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Gemini 3.5 Flash accepts 1,048,576 input tokens compared to Solar Pro 4's 524,288 tokens. Solar Pro 4 can generate longer responses up to 131,072 tokens, while Gemini 3.5 Flash is limited to 65,536 tokens.

Google
Gemini 3.5 Flash
Input1,048,576 tokens
Output65,536 tokens
Upstage
Solar Pro 4
Input524,288 tokens
Output131,072 tokens
Fri Aug 28 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Gemini 3.5 Flash supports multimodal inputs, whereas Solar Pro 4 does not.

Gemini 3.5 Flash can handle both text and other forms of data like images, making it suitable for multimodal applications.

Gemini 3.5 Flash

Text
Images
Audio
Video

Solar Pro 4

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Gemini 3.5 Flash

Proprietary

Closed source

Solar Pro 4

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 3.5 Flash was released on 2026-05-19, while Solar Pro 4 was released on 2026-08-06.

Solar Pro 4 is 3 months newer than Gemini 3.5 Flash.

Gemini 3.5 Flash

May 19, 2026

3 months ago

Solar Pro 4

Aug 6, 2026

3 weeks ago

2mo newer

Knowledge Cutoff

When training data ends

Gemini 3.5 Flash has a documented knowledge cutoff of 2026-01-31, while Solar Pro 4's cutoff date is not specified.

We can confirm Gemini 3.5 Flash's training data extends to 2026-01-31, but cannot make a direct comparison without Solar Pro 4's cutoff date.

Gemini 3.5 Flash

Jan 2026

Solar Pro 4

—

Provider Availability

Gemini 3.5 Flash is available from Google. Solar Pro 4 is available from Upstage.

Gemini 3.5 Flash

google logo
Google
Input Price:Input: $1.50/1MOutput Price:Output: $9.00/1M

Solar Pro 4

upstage logo
Unknown Organization
Input Price:Input: $0.30/1MOutput Price:Output: $1.20/1M
* 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 3.5 Flash and Solar Pro 4 side-by-side, then vote on the output you prefer.

Gemini 3.5 Flash
✓ Preferred
Solar Pro 4
Open in Playground

FAQ

Common questions about Gemini 3.5 Flash vs Solar Pro 4.

Which is better, Gemini 3.5 Flash or Solar Pro 4?

Gemini 3.5 Flash leads the LLM Stats Score 43.6 to 36.0. Gemini 3.5 Flash is made by Google and Solar Pro 4 is made by Upstage. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Gemini 3.5 Flash compare to Solar Pro 4 in benchmarks?

Gemini 3.5 Flash scores CharXiv-R: 84.2%, MCP Atlas: 83.6%, MMMU-Pro: 83.6%, OSWorld-Verified: 78.4%, Terminal-Bench 2.0: 76.2%. Solar Pro 4 scores AIME 2026: 95.3%, GPQA: 89.0%, LiveCodeBench: 87.8%, MMLU-Pro: 86.3%, AA-LCR: 71.0%.

Is Gemini 3.5 Flash cheaper than Solar Pro 4?

Solar Pro 4 is 5.0x cheaper for input tokens. Gemini 3.5 Flash costs $1.50/M input and $9.00/M output via google. Solar Pro 4 costs $0.30/M input and $1.20/M output via upstage.

What are the context window sizes for Gemini 3.5 Flash and Solar Pro 4?

Gemini 3.5 Flash supports 1.0M tokens and Solar Pro 4 supports 524K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Gemini 3.5 Flash and Solar Pro 4?

Key differences include LLM Stats Score (43.6 vs 36.0), context window (1.0M vs 524K), input pricing ($1.50 vs $0.30/M), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes Gemini 3.5 Flash and Solar Pro 4?

Gemini 3.5 Flash is developed by Google and Solar Pro 4 is developed by Upstage.

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