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GPT-5.3 Chat vs GPT-5.6 Sol

GPT-5.6 Sol leads the LLM Stats Score 55.1 to 29.6. GPT-5.3 Chat is 2.3x cheaper per token.

OpenAI · OpenAI · Updated for 2026

Which is better?

GPT-5.6 Sol leads the overall LLM Stats Score 55.1 to 29.6, ranking #3 overall.

In the 2 individual benchmarks reported for both models, GPT-5.6 Sol wins 2; this is a narrower head-to-head signal than the composite indexes.

On price, GPT-5.3 Chat is roughly 2.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-5.6 Sol also accepts a larger context window (1,050,000 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 GPT-5.3 Chat

  • cost matters — it's about 2.3x cheaper per token

Choose GPT-5.6 Sol

  • overall performance matters — it scores 55.1 and ranks #3 on LLM Stats
  • you value its reported benchmark strengths — it wins 2 of 2 exact shared results
  • you process long inputs — it offers a 1,050,000 token context window
  • you want the most recent training data — it shipped Jul 2026

At a glance

The differences that matter most.

Core performance indexes
29.6
#125
55.1
#3
Cost, coverage & limits
Benchmark wins
0 of 2
2 of 2
Input price
$1.75 / M
$5.00 / M
Output price
$14.00 / M
$30.00 / M
Context window
128,000
1,050,000

Individual benchmarks

2 reported for GPT-5.3 Chat · 45 for GPT-5.6 Sol

2 shared

GPT-5.3 Chat outperforms in 0 benchmarks, while GPT-5.6 Sol is better at 2 benchmarks (HealthBench, HealthBench Hard).

GPT-5.6 Sol significantly outperforms across most benchmarks.

Wed Sep 09 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

GPT-5.3 Chat costs less

For input processing, GPT-5.3 Chat ($1.75/1M tokens) is 2.9x cheaper than GPT-5.6 Sol ($5.00/1M tokens).

For output processing, GPT-5.3 Chat ($14.00/1M tokens) is 2.1x cheaper than GPT-5.6 Sol ($30.00/1M tokens).

In conclusion, GPT-5.6 Sol is more expensive than GPT-5.3 Chat.*

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

Lowest available price from all providers
Wed Sep 09 2026 • llm-stats.com
OpenAI
GPT-5.3 Chat
Input tokens$1.75
Output tokens$14.00
Best providerOpenAI
OpenAI
GPT-5.6 Sol
Input tokens$5.00
Output tokens$30.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue

Context Window

Maximum input and output token capacity

GPT-5.6 Sol accepts 1,050,000 input tokens compared to GPT-5.3 Chat's 128,000 tokens. GPT-5.6 Sol can generate longer responses up to 128,000 tokens, while GPT-5.3 Chat is limited to 16,384 tokens.

OpenAI
GPT-5.3 Chat
Input128,000 tokens
Output16,384 tokens
OpenAI
GPT-5.6 Sol
Input1,050,000 tokens
Output128,000 tokens
Wed Sep 09 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both GPT-5.3 Chat and GPT-5.6 Sol support multimodal inputs.

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

GPT-5.3 Chat

Text
Images
Audio
Video

GPT-5.6 Sol

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.

GPT-5.3 Chat

Proprietary

Closed source

GPT-5.6 Sol

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-5.3 Chat was released on 2026-03-04, while GPT-5.6 Sol was released on 2026-07-09.

GPT-5.6 Sol is 4 months newer than GPT-5.3 Chat.

GPT-5.3 Chat

Mar 4, 2026

6 months ago

GPT-5.6 Sol

Jul 9, 2026

2 months ago

4mo newer

Knowledge Cutoff

When training data ends

GPT-5.3 Chat has a knowledge cutoff of 2025-08-31, while GPT-5.6 Sol has a cutoff of 2026-02-16.

GPT-5.6 Sol has more recent training data (up to 2026-02-16), making it potentially better informed about events through that date compared to GPT-5.3 Chat (2025-08-31).

GPT-5.3 Chat

Aug 2025

GPT-5.6 Sol

Feb 2026

6 mo newer

Provider Availability

GPT-5.3 Chat is available from OpenAI. GPT-5.6 Sol is available from OpenAI.

GPT-5.3 Chat

openai logo
OpenAI
Input Price:Input: $1.75/1MOutput Price:Output: $14.00/1M

GPT-5.6 Sol

openai logo
OpenAI
Input Price:Input: $5.00/1MOutput Price:Output: $30.00/1M
* 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 GPT-5.3 Chat and GPT-5.6 Sol side-by-side, then vote on the output you prefer.

GPT-5.3 Chat
✓ Preferred
GPT-5.6 Sol
Open in Playground

FAQ

Common questions about GPT-5.3 Chat vs GPT-5.6 Sol.

Which is better, GPT-5.3 Chat or GPT-5.6 Sol?

GPT-5.6 Sol leads the LLM Stats Score 55.1 to 29.6. GPT-5.3 Chat is made by OpenAI and GPT-5.6 Sol is made by OpenAI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does GPT-5.3 Chat compare to GPT-5.6 Sol in benchmarks?

GPT-5.3 Chat scores HealthBench: 54.1%, HealthBench Hard: 25.9%. GPT-5.6 Sol scores Connectors: 100.0%, Capture-the-Flag Challenges (Internal): 96.7%, HealthBench Consensus: 95.5%, GPQA: 94.6%, MRCR v2 (8-needle): 91.5%.

Is GPT-5.3 Chat cheaper than GPT-5.6 Sol?

GPT-5.3 Chat is 2.9x cheaper for input tokens. GPT-5.3 Chat costs $1.75/M input and $14.00/M output via openai. GPT-5.6 Sol costs $5.00/M input and $30.00/M output via openai.

What are the context window sizes for GPT-5.3 Chat and GPT-5.6 Sol?

GPT-5.3 Chat supports 128K tokens and GPT-5.6 Sol supports 1.1M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GPT-5.3 Chat and GPT-5.6 Sol?

Key differences include LLM Stats Score (29.6 vs 55.1), context window (128K vs 1.1M), input pricing ($1.75 vs $5.00/M). See the full comparison above for benchmark-by-benchmark results.