Now monitoring OpenAI & Anthropic in real time

Never get burned by an API bill again.

API Monitor watches your OpenAI & Anthropic spend every hour and pings your team the moment costs threaten to spiral.

No credit card required · 5-minute setup

api-monitor.app/dashboard

Spend

$1,247

+12% vs last week

Threshold

$2,000

Keys

8

2 providers

OpenAI key approaching threshold

62% used · alerted via #engineering

Weekly spend

7 days

5,000+

API keys monitored

$2M+

overages prevented

99.9%

uptime SLA

Why teams choose us

Built for the API-first era

Three primitives that turn every AI bill into a predictable line item.

Hard spending limits

Set dollar thresholds per API key. When usage gets close, we alert you — before the bill arrives.

Multi-channel alerts

Route to email or any Slack workspace. Each alert can have its own destination, threshold, and recipients.

AES-256 encryption

Keys are encrypted at rest with AES-256-CBC. We never log, expose, or read your API keys after storage.

How it works

From key to alert in three steps

01

Paste your API key

Add an OpenAI or Anthropic key. It is encrypted instantly with AES-256.

02

Configure thresholds

Set the dollar amounts that matter. Pick email, Slack, or both.

03

Get alerted automatically

We poll usage every hour. The moment spend crosses your line, you know.

Notifications

Alerts that meet your team where they are

Route alerts to email or any Slack workspace. Different thresholds, different channels — configured per API key, ready in under a minute.

  • Email alerts to anyone on the team
  • Slack webhooks for channel-specific routing
  • Multiple thresholds (50%, 80%, 100%) per key
  • Hourly polling with zero infrastructure
#engineeringvia Slack

API Monitor · 14:32

OpenAI key crossed 80% of $2,000 limit

$1,612.40 used in the last 7 days

team@company.comvia Email

[Alert] Anthropic spend at $487 / $500

Threshold of 97% reached at 14:31 UTC

Customers

Loved by engineers & founders

We were burning $4,000/month on OpenAI without realizing one endpoint was running inference on every page load. API Monitor caught it in hours.

M

Marcus Reid

CTO, Loopline AI

I manage API keys for 12 clients. Before this tool I was constantly firefighting surprise bills. Now I sleep well knowing each has a hard cap.

P

Priya Sharma

Founder, DevStack Agency

The Slack integration alone is worth it. Our #engineering channel gets a heads-up before any budget is hit. Setup took 5 minutes.

T

Tom Nakamura

Lead Engineer, Fieldnotes

Start monitoring in 5 minutes

No credit card. No infrastructure. Just paste a key and we'll take it from here.

Create free account