Know exactly
what your
AI costs.

Connect OpenAI, Anthropic, and Gemini. Track every dollar spent — by model, by day, by team.

Start for free →
Tracks usage from
OpenAI
Anthropic
Google Gemini
AWS Bedrock
// features

Everything you need to understand your AI spend

No more guessing. No more end-of-month surprises.

01 · Unified tracking

All your providers,
one view.

Connect OpenAI and Anthropic with an Admin API key each. Costly syncs usage data automatically every day.

Daily sync, no code required
Admin keys encrypted with AES-256
Cost breakdown by model and day
01 · unified tracking
gpt-4o
$142.30
claude-3-5-sonnet
$89.10
gemini-1.5-pro
$42.60
gpt-4o-mini
$10.50
02 · Model comparator

What would it cost
with a different model?

Select any time range and Costly recalculates your total spend as if you had used a different model. Find the cheapest option that fits your quality bar.

Compare across providers instantly
Based on your actual token usage
Savings highlighted in green
02 · model comparator
Model
$/1M in
$/1M out
Est. total
gpt-4o (current)
$2.50
$10.00
$142.30
claude-3-haiku
$0.25
$1.25
$53.10save $89
gemini-1.5-flash
$0.075
$0.30
$31.40
gpt-4o-mini
$0.15
$0.60
$48.20
03 · Export & reporting

Your data,
your format.

Export any date range to CSV with one click. Full usage table with model, tokens, and cost per day. Perfect for finance reports and budget tracking.

Export filtered by provider, model, date
Daily granularity, ready for spreadsheets
No lock-in — it's just a CSV
03 · export & reporting
costly-june-2026.csv
842 rows · all providers · 30 days
Download
date, provider, model, input_tokens...
2026-06-01, openai, gpt-4o, 48230...
2026-06-01, anthropic, claude-3-5, 31100...
... 840 more rows
// how it works

Up and running
in 3 minutes.

01

Connect your Admin API key

Paste your Admin API key for each provider. Keys are encrypted with AES-256 on the server — never exposed to the client.

provider: "anthropic"
key: sk-ant-admin01-••••
02

Costly syncs automatically

We pull your usage data from each provider daily. No code changes, no manual imports.

last_sync: "2m ago"
records: 842 rows
03

Analyze and optimize

See breakdowns by model, compare costs across providers, and export to CSV for your finance team.

potential_savings: $89/mo
recommendation: haiku

Stop guessing.
Start knowing.

Join developers who already have their AI costs under control. Free to start, no credit card required.

Start for free →

Free forever for individual use · GitHub or Google sign in