GPT-5.6 Sol API Pricing & Cost Calculator

GPT-5.6 Sol is OpenAI's flagship-tier play. Compared to GPT-5.6 Terra's list price ($2/$12), it costs 2.5x on input and 2.5x on output - it only pays off when you actually need frontier reasoning.

GPT-5.6 Sol is OpenAI's premium reasoning tier in the 5.6 generation, alongside Terra (workhorse) and Luna (ultra-cheap). It competes directly with Claude Opus 5 at $5/$30.

By TechCompare · Updated

Input tokens
100,000
50% cached
Output tokens
5,000
per request
Volume
100 / monthly
Standard API

Calculator

Cost Comparison

Based on 100,000 input tokens (50% cached), 5,000 output tokens, and 100 requests.

How this is calculated

GPT-5.6 Sol is priced at $5.00 per million input tokens and $30.00 per million output tokens, matching GPT-5.5's rate. It supports a 90% prompt caching discount ($0.50 per million) and a 50% batch discount ($2.50 per million inputs, $15.00 per million outputs) via OpenAI's Batch API.

Verdict

GPT-5.6 Sol is OpenAI's flagship-tier play. Compared to GPT-5.6 Terra's list price ($2/$12), it costs 2.5x on input and 2.5x on output - it only pays off when you actually need frontier reasoning.

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Frequently asked questions

Should I pick GPT-5.6 Sol or GPT-5.6 Terra?
Sol ($5/$30) for hard reasoning tasks; Terra ($2/$12 list price, though OpenRouter sometimes shows temporary discounts) for high-volume everyday workloads. Sol's premium only earns its keep on the most demanding agentic chains where Terra's reasoning falls short.