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Cost Forecast
Projects your AWS spend forward using historical billing data and AI-powered analysis.
Last updated: May 2025
The Forecast page projects your AWS spend forward using your historical billing data and an AI narrative powered by Claude. It surfaces cost problems before they appear on your invoice — giving you time to act rather than explain.
Forecast horizon
| Mode | Description |
|---|---|
| Monthly | Projects 1 month ahead. Best for catching next-month surprises before the bill lands. |
| Quarterly | Projects 3 months ahead. Useful for quarterly business reviews and budget headroom requests. |
Reading the chart
| Element | Description |
|---|---|
| Solid indigo line | Your actual monthly spend for the last 1–3 months |
| Dashed amber line | Projected spend for the selected horizon (1 or 3 months) |
| Shaded amber band | 90% confidence interval — wider band means less history is available |
| Vertical dashed line | Marks where actuals end and projections begin |
KPI cards
| Card | Description |
|---|---|
| Next Month Projection | Estimated total AWS spend for the coming calendar month |
| 3-Month Total | Cumulative projected spend over the next quarter (quarterly mode only) |
| Last Month Actual | Your most recent complete month — the baseline for the projection |
| Potential Savings | Total estimated savings from AI-identified optimization opportunities |
Confidence levels
| Level | Meaning |
|---|---|
| High | 3+ months of data. Projections are reliable — act on them. |
| Medium | 2 months of data. Directionally correct; treat numbers as a range. |
| Low | Less than 2 months. Sync billing data and return next month for a reliable projection. |
AI Analysis panel
| Section | Description |
|---|---|
| Summary | 2–3 sentence overview of your cost direction, the primary driver, and the key takeaway |
| Risk Flags | Services with >30% projected growth or sudden spend spikes. Hidden when none exist. |
| Optimization Opportunities | Ranked list of actions from your active recommendations with estimated savings and effort level |
| Key Drivers | Top 3–5 services contributing most to your bill with a trend percentage and plain-English explanation |
When to use the Forecast
- Before month-end — check if spend is tracking above last month and investigate before the invoice arrives
- Before a quarterly review — give finance a projected 3-month number instead of extrapolating manually
- After a major infrastructure change — trigger a billing sync, then refresh the forecast to see the impact
- When evaluating a recommendation — the Optimization Opportunities list shows exactly how much you'd save by acting on each pending item
Limitations
- New accounts — requires at least 2 months of synced data; confidence will show as Low until then.
- One-off events — a large one-time charge (e.g. Reserved Instance purchase) distorts the trend line. The Risk Flags section typically calls this out.
- In-flight changes — a new service launch won't appear in the trend until the next billing sync captures its spend.
- Monthly granularity — the forecast does not predict daily or weekly fluctuations.
Troubleshooting
| Symptom | Fix |
|---|---|
| No billing data available | Go to Accounts and click Sync on your account |
| Confidence shows Low | Sync billing data — return after another calendar month |
| AI Analysis section missing | ANTHROPIC_API_KEY is not configured — contact your administrator |
| Numbers look stale | Click Refresh in the top-right corner |
| Projected spend seems too high | A one-time spike may be skewing the trend. Check Risk Flags. |