GPT-5.6 Sol vs DeepSeek V4 Pro

Closed flagship against the open-weight challenger that undercuts it dramatically on price.

What the numbers say

Derived from the live registry Zeplik routes and bills against. Credits: 1 credit = $0.10, raw provider rate with a 1.10x margin.

Side by side

GPT-5.6 Sol

OpenAI

GPT-5.6 Sol is the flagship model in OpenAI's GPT-5.6 series. It is suited for complex reasoning, coding, and agentic workflows, and is particularly strong at command-line and multi-step coding tasks...

Provider
OpenAI
Context window
1.1M tokens
Input price
55.0 credits / 1M tokens ($5.00 raw)
Output price
330 credits / 1M tokens ($30.00 raw)
Vision (image input)
Yes
Tool calling
Yes
Extended reasoning
No

Best for

  • Hard problems where answer quality matters more than cost: strategy, analysis, difficult writing
  • Very long documents and codebases: a 1.1M-token window fits entire books or repositories in one conversation
  • Working with images: screenshots, charts, photos and scanned documents alongside text
  • Tool use and agents: reliably calls functions, so it can search, run skills and drive workflows

DeepSeek V4 Pro

DeepSeek

DeepSeek V4 Pro is a large-scale Mixture-of-Experts model from DeepSeek with 1.6T total parameters and 49B activated parameters, supporting a 1M-token context window. It is designed for advanced reasoning, coding,...

Provider
DeepSeek
Context window
1.0M tokens
Input price
4.8 credits / 1M tokens ($0.43 raw)
Output price
9.6 credits / 1M tokens ($0.87 raw)
Vision (image input)
No
Tool calling
Yes
Extended reasoning
No

Best for

  • Everyday chat and drafting on an open-weight model with transparent lineage
  • Very long documents and codebases: a 1.0M-token window fits entire books or repositories in one conversation
  • Tool use and agents: reliably calls functions, so it can search, run skills and drive workflows

Try both on Zeplik

The honest answer to most model debates is to run your own prompt on both. Zeplik puts GPT-5.6 Sol and DeepSeek V4 Pro in the same chat, so you can switch mid-conversation and compare answers on the work you actually do.

Pick a model and ask. Your prompt opens in the Zeplik app with that model selected.

Model to ask
GPT-5.6 Sol vs DeepSeek V4 Pro - Which AI Model to Use | Zeplik Chat