FOCUS is the FinOps Foundation's open billing format. AWS, Azure and Google Cloud can export it, so cloud costs from different providers land in the same columns. AI providers don't export it yet, and their CSVs don't map cleanly.
The cached-token trap
Anthropic's Console splits input tokens into four buckets, each at a different price:
| Token type | Price relative to base input |
|---|---|
| Uncached input | 1x |
| Cache read | 0.1x |
| Cache write, 5 minutes | 1.25x |
| Cache write, 1 hour | 2x |
OpenAI does it differently: cached tokens are counted inside prompt tokens. If you treat both exports the same way, you either count cached input twice (OpenAI) or lose the cache writes (Anthropic). Cache writes are billed, not just reported, which surprises people.
One row per meter
The fix is to give every token type its own row, its own SKU and its own unit price, like a cloud bill does for each meter. Here's one real day from my own October Anthropic export after conversion (a few of the 40 columns shown; prices are per million tokens):
| ChargePeriodStart | SkuId | SkuMeter | ConsumedQuantity | ListUnitPrice | BilledCost |
|---|---|---|---|---|---|
| 2026-10-28 | anthropic/claude-sonnet-4-5/input | Input Tokens | 52 | 3.00 | 0.000156 |
| 2026-10-28 | anthropic/claude-sonnet-4-5/cache-read | Cache Read Input Tokens | 5,775 | 0.30 | 0.0017325 |
| 2026-10-28 | anthropic/claude-sonnet-4-5/cache-write-5m | Cache Write Input Tokens (5 min) | 1,925 | 3.75 | 0.00721875 |
| 2026-10-28 | anthropic/claude-sonnet-4-5/output | Output Tokens | 16 | 15.00 | 0.00024 |
| 2026-10-28 | anthropic/claude-haiku-4-5/cache-write-5m | Cache Write Input Tokens (5 min) | 23,016 | 1.25 | 0.02877 |
Look at the Sonnet rows: 52 uncached input tokens, but 7,700 tokens went through the cache. A converter that only reads "input tokens" reports 52 and misses most of that day's input cost. The 1-hour cache write gets its own .../cache-write-1h row when it appears; this month's file didn't have any.
The total of the rows has to match the provider's own figure. If the computed price doesn't round to the cost in the export, the converter trusts the provider's number and records that it did so.
For the whole month: 41 rows, $1.06 in FOCUS BilledCost against $1.06 on Anthropic's own cost export.
Try it
For Anthropic, pass both the Cost and the Usage exports from the Console:
npx ai-bill-to-focus convert cost.csv usage.csv -o focus.csv
npx ai-bill-to-focus check focus.csv
Or in the browser, where the file never leaves your machine: https://www.cognocient.com/tools/focus-checker
What isn't tested yet
Anthropic is tested on real Console exports. OpenAI and Together AI are built from their published formats, and I haven't had a real file. If you have one, npx ai-bill-to-focus report <your files> prints a summary with no dollars or account names that you can paste into an issue.
Repo (MIT): https://github.com/mandarvshinde/ai-bill-to-focus
I build Cognocient AI, which tracks AI spend per feature, team and customer. This tool is standalone and needs no account.
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