Solutions

Cheap GPT-5.6 Sol API

GPT-5.6 Sol is OpenAI's ChatGPT model listed at $5 / $30 per 1M input/output tokens. Through Somnus every top-up is credited at 2× to 2.5×, so you effectively pay $2.5 / $15 or less, on the same OpenAI-compatible key as 50+ other models.

What a top-up buys on GPT-5.6 Sol

You payCredit≈ 1M output tokens of GPT-5.6 Sol
$20 (2×)$401.3
$50 (2.2×)$1103.7
$100 (2.35×)$2357.8
$200 (2.5×)$50017

Output-token count only; input tokens are cheaper. First top-up is at least 2.5×.

When to pick GPT-5.6 Sol

GPT-5.6 Sol costs $0.02 per 1,500-in/500-out request at list price, $0.01 effective. It is a premium model: use it for the hardest reasoning and writing, and route simple tasks to a cheaper model.

GPT-5.6 Sol vs similarly priced models

ModelMakerList (in / out)EffectiveSame request, effective
Claude Opus 5Anthropic$5 / $25$2.5 / $12.5$0.01
Claude Opus 5.5Anthropic$4 / $20$2 / $10$0.0080
Kimi K3Moonshot$3 / $15$1.5 / $7.5$0.0060
Gemini 3.1 ProGoogle$2 / $12$1 / $6$0.0045

Nearest models to GPT-5.6 Sol by blended price (3 input : 1 output). All run on one Somnus key.

Getting the most out of GPT-5.6 Sol for less

  • Input is 6.0× cheaper than output on GPT-5.6 Sol, so long context with short answers is the cheapest pattern.
  • A $200 top-up gives $500 credit — about 44M blended GPT-5.6 Sol tokens.
  • Mix models: send easy steps to DeepSeek V4 Flash and keep GPT-5.6 Sol for the steps that need it.

Other ChatGPT models on Somnus

ModelList (in / out)Effectivevs GPT-5.6 Sol
GPT-6 Astra$10 / $50$5 / $251.78× the price
GPT-5.6 Luna$1 / $6$0.5 / $30.20× the price

Every OpenAI model shares the same key and balance.

Use GPT-5.6 Sol

javascript
import OpenAI from "openai";

const client = new OpenAI({
  apiKey: process.env.SOMNUS_API_KEY,
  baseURL: "https://gateway-production-c837.up.railway.app/v1",
});

const resp = await client.chat.completions.create({
  model: "claude-sonnet-5",
  messages: [
    {"role": "user", "content": "Summarise this in one line"}
  ],
});
console.log(resp.choices[0].message.content);

Copy the exact model id from your dashboard.

Questions

Is GPT-5.6 Sol really cheaper on Somnus?

Usage is billed at OpenAI's list price, but each dollar you pay is credited as $2–$2.50, so the effective price is half or less.

Do I need a subscription?

No. Top up any amount from $5, or start with the free $5 credit.

Is Somnus affiliated with OpenAI?

No. Somnus is an independent gateway.

Try GPT-5.6 Sol with free credit

$5 free on sign-up, then 2× or more on every top-up.

Create a free account

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