Vertex AI API
Vertex AI API is Google's programmatic interface for developers — tracked here as part of TheLLMWiki's index of 27 public AI APIs. This page is a starting point for evaluating Vertex AI API: what models it serves, how to get started, where to find live pricing, and how it stacks up against comparable APIs from other vendors.
Using Vertex AI API
Like most model APIs, Vertex AI API bills per token, often offers a prompt-caching or batch discount on repeated or non-urgent workloads, and documents rate limits and authentication in Google's own developer docs — always the source of truth for current pricing and limits. Use this page as an index of what Vertex AI API serves and how it fits into the wider Google ecosystem, not as a live pricing reference.
Most teams start by prototyping directly against Vertex AI API using the vendor's official SDK, then move to production once they've confirmed latency, cost per request at real volume, and output quality on their actual prompts — not a public benchmark.
What Vertex AI API runs
Models from Google accessible through this API, tracked in our model index.
A practical path to your first Vertex AI API call
- Create an account and generate an API key from Google's developer console
- Install the official SDK for your language rather than calling raw HTTP where one exists
- Start with a small, cheap model in the family to validate your integration before switching to the flagship
- Set a hard budget alert before running anything at real volume
- Read the rate-limit documentation before you hit it in production
How Vertex AI API is typically billed
Most APIs in this category bill per million tokens, split into an input rate and a (usually higher) output rate, with a separate, cheaper rate for cached or repeated input. Some also offer a batch tier at a discount for non-urgent, asynchronous workloads. Because these numbers change with almost every model update, always confirm the current rate on Google's official pricing page before estimating a production budget — treat any specific number you see elsewhere, including summaries like this one, as a starting point rather than a quote.
Vertex AI API, answered
What does Vertex AI API give you access to?
Programmatic access to Google's models, including Gemini 2.5 Pro, Gemini 2.5 Flash, Gemini 2.0 Flash, Gemini 1.5 Pro.
Is pricing on this page current?
Always confirm against Google's live pricing page before budgeting — API pricing changes with nearly every model release.
How does Vertex AI API compare to other APIs?
See our comparison hub for head-to-head breakdowns across vendors, or the related APIs listed above.
Do I need a business account to use this API?
Most providers let individual developers sign up directly with a personal account; enterprise agreements are usually only needed for volume discounts, SLAs, or dedicated support.
What's the fastest way to estimate my costs?
Run a representative sample of your real requests, note the average input and output token count per request, then multiply by the current published rate — not a rough guess based on word count.
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