Hard spend limits for Claude API projects, with automatic cutoff the second you cross budget.

Anthropic does not offer per-key budget caps. One failed loop can burn hundreds overnight. Claude Usage Cap gives each project a dedicated proxy key with daily, weekly, and monthly limits plus Slack alerts when blocking starts.

What you get

Purpose-built for dev workloads and SaaS products using Claude.

Real-time usage ledger

Track spend per request using model-aware token pricing.

Instant 429 cutoff

Proxy blocks new calls the moment a cap window is exhausted.

Slack incident alert

Notify your team when a project is being blocked by budget rules.

Problem

Teams ship experiments quickly, and a single infinite retry loop can consume large API spend before anyone notices.

Solution

Route traffic through a project proxy key that enforces budget caps before forwarding to Claude.

Outcome

Experimental workloads stay inside predefined spend boundaries without manual monitoring.

Simple pricing

One flat subscription per protected project.

$15/project/month

Daily, weekly, and monthly cap enforcement
Per-project proxy key issuance and rotation support
Slack alert on blocked requests
Usage dashboard and 30-day spend chart

FAQ

How does cutoff work?

Every request to Claude goes through your project proxy key. Before forwarding, we check period spend totals in real time. If a cap is reached, the proxy immediately returns 429 and your workload stops.

Does this replace Anthropic billing?

No. Anthropic remains the billing provider. Claude Usage Cap is a guardrail layer that blocks requests once your configured project cap is exhausted.

What if I run multiple apps on one Anthropic account?

Create one project per app, service, or environment. Each gets its own proxy key and independent daily, weekly, and monthly caps.

How quickly do Slack alerts fire?

The alert is sent when the first blocked request occurs for an exceeded period. We deduplicate alerts per period window to avoid spam.