The complete OpenAI model lineup — GPT-6.1, GPT-5.6 and everything back to GPT-3.5, plus the o-series reasoning models, all accessible through a single API.
Guides, comparisons and pricing analysis from the APIMart blog.
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gpt-6.1-sol
Transparent pricing with no hidden fees. Pay only for what you use.
Per 1M tokens
Up to 272,000 input tokens
| Rate | GoldCurrent price | Platinum | Diamond | Official | Your savings |
|---|---|---|---|---|---|
| Input | 16~$1.6 | 15.2~$1.52 | 14.4~$1.44 | 20~$2 | 20% |
| Cached input | 1.6~$0.16 | 1.52~$0.152 | 1.44~$0.144 | 2~$0.2 | 20% |
| Cache write | 20~$2 | 19~$1.9 | 18~$1.8 | 25~$2.5 | 20% |
| Output | 80~$8 | 76~$7.6 | 72~$7.2 | 100~$10 | 20% |
Over 272,000 input tokens
| Rate | GoldCurrent price | Platinum | Diamond | Official | Your savings |
|---|---|---|---|---|---|
| Input | 32~$3.2 | 30.4~$3.04 | 28.8~$2.88 | 40~$4 | 20% |
| Cached input | 3.2~$0.32 | 3.04~$0.304 | 2.88~$0.288 | 4~$0.4 | 20% |
| Cache write | 40~$4 | 38~$3.8 | 36~$3.6 | 50~$5 | 20% |
| Output | 140~$14 | 133~$13.3 | 126~$12.6 | 175~$17.5 | 20% |
Access the full range of OpenAI models including GPT-6.1, GPT-6, and o-series reasoning models. From fast chat to deep reasoning, find the right model for every task.
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Generate an API key to access models programmatically.
Use the playground above or integrate via API with the OpenAI SDK.
What developers say about our GPT API
“Switching to APIMart saved us 40% on GPT-4o costs without any code changes — just swapped the base URL.”
Alex Chen
Backend Engineer
“The o3 model handles our legal document analysis with impressive accuracy. Game changer for our compliance team.”
Sarah Jones
Product Manager
“GPT-5 Codex is incredible for automated code reviews. It catches things our linters miss.”
Mike Brown
Engineering Lead
“We use GPT-4o-mini for real-time chat and o3-mini for background reasoning tasks. Best of both worlds.”
Emily Zhang
AI Engineer
“Reliable API. Documentation is clear and the playground makes testing easy.”
David Li
Startup Founder
“The pricing is significantly better than going direct. Highly recommended for startups watching their budget.”
Lisa Wang
Full Stack Developer
Common questions about using the GPT API
We offer the full OpenAI lineup, led by the latest GPT-6.1 Sol, GPT-6 Sol, GPT-6 Luna, GPT-6 Astra, and GPT-5.6 (Sol, Luna, Terra), plus GPT-5.5, GPT-5.4 (Pro, Mini, Nano), and GPT-5.3 Codex. Earlier models such as GPT-5, GPT-4o, GPT-4.1, GPT-3.5 Turbo, and the o-series reasoning models (o1, o3, o4-mini) remain available.
The o-series (o1, o3, o4-mini) are OpenAI's reasoning models that use chain-of-thought to solve complex problems in math, science, and coding.
Pricing is based on token usage (input + output). Each model has different rates — check the pricing table above for details.
Yes. Our API is fully compatible with the OpenAI SDK. Just change the base URL to start using APIMart.
Yes. We do not store or use your API data for training. All requests are encrypted in transit.
For the newest generation, start with GPT-6.1 Sol or GPT-6 Sol. For fast, low-cost tasks, use GPT-5.4 Mini or GPT-5.4 Nano. For complex tasks, use GPT-5.4 Pro. For coding, try GPT-5.3 Codex or GPT-5.1 Codex Max.
The GPT-5.6 API on APIMart offers three OpenAI model IDs: gpt-5.6-sol, gpt-5.6-luna and gpt-5.6-terra. All three use the same Chat Completions request format and are billed per input and output token, so compare their rates in the pricing table above, test them in the playground, and switch by changing the model ID. The GPT-5.5 API (gpt-5.5) is also available.
The OpenAI GPT API on APIMart is billed per token, with input and output priced separately for each model, including GPT-6.1, GPT-5.5 and the Codex models. The pricing table on this page shows the current rate for every model as Gold member prices (20% off), and Platinum and Diamond members save up to 28%.
Yes. Prices shown on this page are Gold member prices, already 20% off. Platinum and Diamond members save even more, up to 28%, and you only pay for successful requests.
Sign up for APIMart, open the API Keys page in your dashboard and create a new key. The same key calls the OpenAI GPT API and every other model on the platform, with pay-as-you-go billing and no subscription.
Create an APIMart API key, point the OpenAI SDK (or any HTTP client) at APIMart's base URL, and set model to the GPT model you want, such as GPT-6.1 Sol or GPT-5.5. Requests use the standard Chat Completions format, and endpoint details, parameters and code examples are in the APIMart docs (docs.apimart.ai).
No. APIMart does not offer free credits for the GPT API. OpenAI GPT models, including GPT-5.3 Codex, are pay-as-you-go by token usage, you only pay for successful requests, and Gold members get 20% off all prices.
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