Compare GPT 5.6 Sol from OpenAI and Mercury 2.5 Preview from Inception on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the AIHubMix API.
GPT 5.6 Sol
Mercury 2.5 PreviewGPT‑5.6 Sol sets a new standard for both intelligence and efficiency, achieving state-of-the-art results across coding, knowledge work, cybersecurity, and science while outperforming previous and competing frontier models with fewer tokens and at lower estimated cost.
Mercury 2.5 is the latest diffusion-based large language model (dLLM) released by Inception. It is the fastest inference LLM; unlike the sequential token-by-token generation approach, Mercury 2.5 can generate and optimize multiple tokens in parallel, achieving a generation speed of 1,107 tokens per second on standard GPUs. Compared to Mercury 2, its intelligence has increased by more than 10 percentage points, and its quality rivals leading cost-optimized frontier models such as GPT-5.6 Luna (Low), Gemini 3.5 Flash-Lite, and Claude Haiku 4.5.
Prices are per million tokens. Time to First Token and throughput are rolling averages measured on AIHubMix.
Promotional prices show the discounted rate; see each model page for promotion windows.
Daily traffic served through AIHubMix — how demand for each model is trending.
Measured on real AIHubMix traffic, hourly buckets. Gaps mean no traffic in that hour.
Estimate your monthly bill for the same workload on each model.
Monthly = daily × 30. Discounted rates applied where a promotion is active.
Mercury 2.5 Preview: $0.15/M output tokens; GPT 5.6 Sol: $20/M. Use the cost calculator above to estimate your own workload.
Mercury 2.5 Preview: 3.7s time to first token measured on AIHubMix; see the live performance charts above for how each model behaves across the day.
GPT 5.6 Sol accepts 1,050,000 and Mercury 2.5 Preview accepts 260,000 input tokens. Maximum output per request is 128,000 tokens on GPT 5.6 Sol and 65,536 tokens on Mercury 2.5 Preview.
Mercury 2.5 Preview at 110.1 tok/s and GPT 5.6 Sol at 50.1 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.
GPT 5.6 Sol accepts text and image input and supports tool calling, thinking and structured outputs; Mercury 2.5 Preview accepts text input and supports thinking and tool calling.
Yes. AIHubMix serves every model on this page behind one OpenAI-compatible endpoint, so switching between them is a one-line change to the model field — no second account, key or SDK.
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