OpenAI API

The OpenAI API lets you send requests to OpenAI’s models from a script, a spreadsheet or an app instead of typing into ChatGPT. It covers text generation, embeddings, image generation, and speech-to-text with Whisper and newer transcription models. You pay for what you use, mostly by the token.

How it works

You create an account on the OpenAI platform, add billing and generate an API Key. Your code sends a request with the model name, your instructions and the input, and receives a structured response. OpenAI provides official Python and JavaScript libraries; as of 2026 its recommended endpoint for new text projects is the Responses API, with the older Chat Completions endpoint still supported.

Useful settings include the system or developer instructions, structured outputs (forcing JSON that matches a schema), tool calling, and batch processing for large jobs at a lower price.

How it’s used in SEO and marketing

• Rewriting or drafting titles and meta descriptions, then checking them against rules in code.
• Generating content briefs from a keyword universe, as in the Semantic Keyword Research course lab.
• Classifying keywords, reviews or pages into custom labels when no ready-made model exists.
• Transcribing podcasts, webinars and videos for repurposing and YouTube SEO.
• Creating embeddings for clustering, internal linking or semantic search.
• Checking how ChatGPT answers questions about your brand, as part of AI visibility tracking.

Example

In How to Automatically Optimize your SEO Metadata with FuzzyWuzzy and OpenAI in Google Colab, titles and meta descriptions are first compared with FuzzyWuzzy to find weak or duplicated ones; only those are sent to the OpenAI API with instructions to rewrite them. Combining a cheap rule-based filter with an LLM keeps costs down and leaves the decisions reviewable.

Limitations and things to watch

• Model names, prices and endpoints change often. Check the official docs and pricing page before you budget, and update old notebooks that call retired models.
• Outputs vary between runs and can be wrong. Keep a human review step for anything published.
• Do not send personal or confidential data without checking your data-processing terms.
• API usage is billed separately from a ChatGPT subscription.

Learn it on MLforSEO

• How to Automatically Optimize your SEO Metadata with FuzzyWuzzy and OpenAI in Google Colab
• How to transcribe audio with OpenAI’s Whisper API in Google Colab (Python)
• How to use generative AI with structured data for programmatic SEO
• Semantic ML-enabled Keyword Research