Your app sends a request
Your application routes an LLM request through LLM Killswitch before it reaches the model.
AI SPEND PROTECTION
Stop runaway AI costs before they become expensive.
Set a hard spending limit between your application and your AI providers. K-Fuse monitors AI API spending and blocks requests that would exceed your budget.
Protect My AI Spend →Self-hosted · 3-minute setup · Your API keys stay yours
K-FUSE
LIVE
YOUR APP
→ K-FUSE →
AI PROVIDER
DAILY SPEND
$7.42 / $10.00
74%
Budget used
REQUEST
model
claude-sonnet
estimated
$0.83
status
✓ ALLOWED
NEXT REQUEST
PRODUCT IN ACTION
See exactly what K-Fuse protects.
Monitor your AI spending, inspect requests, and see exactly when K-Fuse allows or blocks a request.
Works with
your favorite AI models
How it works
Protect every request before it runs.
LLM Killswitch gives your team a clear, predictable way to control AI spend in real time.
Cost is estimated
We estimate the worst-case token cost so there are no surprises after the request runs.
Your daily budget is checked
The estimated cost is compared with the budget you set for the day.
Allow or block
Requests within budget continue. Requests that exceed it are blocked before they create cost.
LLM Killswitch
Control your AI spend before it happens
Set clear limits around every OpenAI request and keep your infrastructure predictable.
Worst-case cost reservation
Reserve the maximum possible cost before each request is sent.
Daily budget enforcement
Automatically block requests when your daily spending limit is reached.
Self-hosted on Cloudflare Workers
Keep full control of the infrastructure by running it in your own Cloudflare account.
Real-time decisions
Evaluate every request in real time without adding meaningful latency.
Native OpenAI compatibility
Works with the OpenAI API natively, with no application rewrite required.
Zero surprise bills
Make AI usage predictable with guardrails that prevent unexpected charges.
Architecture
Built for your infrastructure
LLM Killswitch runs entirely inside your own Cloudflare Workers deployment, giving you a lightweight control layer with no third-party data sharing.
01 / Source
Your application
Sends an LLM request
02 / Runtime
LLM Killswitch
Runs on Cloudflare Workers
03 / Policy
Cost vs. budget
Estimated cost · Budget available
04 / Destination
OpenAI API
Allowed requests continue
Every request is evaluated before it reaches the model provider.
K-FUSE
One simple way to protect your AI budget.
K-Fuse AI Spend Protection
Protect your AI API budget with a self-hosted spend guard.
LLM Killswitch
Frequently asked questions
Answers about how LLM Killswitch works, data privacy, supported AI providers, daily budget setup, and what happens when your limit is reached.
How does LLM Killswitch work?
It acts as a proxy between your app and the OpenAI API, estimating worst-case token costs before each request and blocking them if your daily budget would be exceeded.
Is my data shared with third parties?
No. LLM Killswitch runs entirely inside your own Cloudflare Workers deployment. Your requests never touch our servers.
Which AI providers are supported?
Currently OpenAI is supported. More providers coming soon.
How do I set my budget?
You configure a daily budget in your Cloudflare Worker environment variables. No dashboard needed.
What happens when the budget is reached?
Requests are blocked immediately and your app receives a clear error response.