Free credits / metered
vx/Vertex AI
Vertex AI — $300 free credits, 90 days for new GCP.
cloud.google.comQuick setup
Open the kRouter dashboard at http://localhost:20128
Go to Providers → click Vertex AI
Paste your API key, click Save
Test the connection
Use in your IDE
Point any OpenAI-compatible client at kRouter using your local API key.
# Endpoint
http://localhost:20128/v1
# API key (from Dashboard → API Keys)
sk-krouter-XXXX
# Model
vertex/gemini-3.1-pro-previewHow Vertex AI billing works with kRouter
Vertex AI gives you free starting credits, then bills per token. kRouter tracks the remaining quota and fails over to another provider before you hit a wall. kRouter authenticates it via apikey. 4 models are routable as vertex/<model>.
Through kRouter, Vertex AI serves chat and code completion. Requests reach it through the same local OpenAI-compatible endpoint as every other provider, so switching to or from Vertex AI is a one-line model change in your client rather than a rewrite.
New Google Cloud accounts get $300 free credits. Requires GCP project + Service Account with Vertex AI API enabled.
Vertex AI models & pricing
Prices are USD per 1M tokens, cheapest first. kRouter bills nothing on top; this is the provider's own rate.
| Model | Route as | Input /1M | Output /1M |
|---|---|---|---|
| Gemini 2.5 Flash | vertex/gemini-2.5-flash | $0.30 | $2.50 |
| Gemini 3.1 Pro Preview | vertex/gemini-3.1-pro-preview | $0.50 | $3.00 |
| Gemini 3.1 Flash Lite Preview | vertex/gemini-3.1-flash-lite-preview | $0.50 | $3.00 |
| Gemini 3 Flash Preview | vertex/gemini-3-flash-preview | $0.50 | $3.00 |
Vertex AI links
Vertex AI FAQ
Is Vertex AI free through kRouter?
Vertex AI is pay-per-token: you bring your own API key and are billed by Vertex AI at their rates. kRouter adds nothing on top and is free and MIT-licensed.
How do I use Vertex AI with Claude Code or Cursor?
Connect Vertex AI in the kRouter dashboard, then point your tool at kRouter's local endpoint (http://localhost:20128/v1) with a kRouter API key. Any OpenAI-compatible client works, and models are addressed as vertex/<model>.
Which Vertex AI models can kRouter route to?
4 models, including Gemini 3.1 Pro Preview, Gemini 3.1 Flash Lite Preview, Gemini 3 Flash Preview. Every one is addressed as vertex/<model> from any client.
What happens when Vertex AI is rate limited?
kRouter detects the limit, parks that account until its real reset time, and fails over to your next connected account or provider — so the request still completes instead of erroring.