> ## Documentation Index
> Fetch the complete documentation index at: https://docs.oncost.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Cost Explorer

> Drill into your costs by any dimension

# Cost Explorer

The Cost Explorer lives under **Spend > Explorer**. It's a flexible query tool for slicing your costs by service, region, account, tag, or any combination.

## Grouping and filtering

* **Group by** -- pick a dimension: service, region, account, sub-service, billing model, or tag
* **Filters** -- narrow by provider, date range, service, region, billing model, or tag key=value
* **Granularity** -- daily or monthly aggregation
* **Date range** -- presets (Last 7 days, This Month, Last Month, etc.) or custom range

## Period comparison

Every row shows a **vs. prior period** column:

* Percentage change and absolute dollar change
* Color-coded: increases in red, decreases in green
* "New" badge for services that didn't exist in the prior period

Toggle comparison on/off with the switch in the filter bar.

## Sparklines

Each row includes a mini trend chart showing the cost trajectory over the selected period.

## Progressive drill-down

Click any row to drill deeper. For example:

1. Start grouped by **service** -- click "Amazon EC2"
2. Now grouped by **region** within EC2 -- click "us-east-1"
3. Now grouped by **account** within EC2 in us-east-1
4. Continue to **resource ID** level

A breadcrumb bar tracks your drill-down path. Click any breadcrumb to go back.

The full drill-down state is encoded in the URL, so you can share or bookmark any view.

## Billing model grouping

Group by **billing model** to see how your costs split across subscription, usage, and commitment categories:

* **Subscription** -- fixed recurring charges (e.g., Anthropic Pro plan, OpenAI Plus plan, GitHub Copilot seats)
* **Usage** -- pay-as-you-go charges (e.g., API tokens, AWS on-demand compute, GCP services)
* **Commitment** -- prepaid commitments (e.g., AWS Reserved Instances, Savings Plans)

Use the billing model filter to isolate a single category. For example, filter to "subscription" to see all your fixed SaaS costs across providers in one view.

## Saved views

Save frequently-used filter + grouping combinations:

1. Set up your desired filters and grouping
2. Click **Save View** in the toolbar
3. Name it (e.g., "ML Team by Model", "Production AWS by Region")

Access saved views from the dropdown in the Explorer toolbar. Views are shared across your team.

## Export

Click **Export CSV** to download the current view. When comparison is enabled, the export includes the comparison columns.