Cloud Cost Forecasting

Cloud Cost Forecasting

Forecasting projects your future cloud spend from your recent history. Xplorr fits a linear trend to your daily spend and projects it 60 days ahead, for the whole organization or one account. A seasonal view adjusts that projection for day of week patterns.

How it works

Linear model

Xplorr runs an ordinary least squares (OLS) regression on up to 90 days of daily spend before the forecast month’s end. Only complete days are used, so today’s partial billing data cannot drag the trend down. The trend line is projected forward 60 days.

The model gives you:

• Projected end of month spend: what the current month will likely total
• Trend direction: increasing, decreasing or flat

Seasonal view

Some workloads have weekly patterns, such as lower spend on weekends. Switch the chart to Seasonal forecast to apply day of week multipliers, taken from your complete historical days, to the linear projection. You choose the model; Xplorr does not switch automatically.

What you see in the console

Open Forecast from the left sidebar in the console. The page shows:

• Month to date spend: actual spend so far this month
• Projected end of month spend: where the month is heading
• Trend indicator
• Historical spend and 60-day forecast chart
• Forecast accuracy: how past forecasts, saved daily, compared with the spend that actually arrived

Budget integration

Forecasting ties into your budgets. A budget with its Forecast alert switch on (the default) alerts when spend is projected to exceed the budget by the end of its period, even if actual spend hasn’t reached it yet. The check runs daily at 11:00 UTC.

Forecast alerts go through the same channels as budget alerts: email to admins, and Slack. See Budget Alerts.

Step-by-step: using forecasts for planning

1. Check the forecast weekly. Open the Forecast page and review the projected end of month spend for your organization. Compare it to your budget.

2. Narrow to an account. If the overall trend is up, select one account to see which is driving the increase, then use Cost Analysis to find the service.

3. Combine with recommendations. If the forecast shows you’ll exceed budget, check the Recommendations page for idle resources and other quick wins.

4. Turn on the forecast alert. Go to Budgets, edit your budget, and make sure Forecast alert is on.

5. Review accuracy. Check the forecast accuracy panel. If it is consistently off, you probably have volatile workloads (like spot instances or batch jobs) that a linear trend can’t capture well.

Common mistakes

• Relying on the forecast in the first days of the month. Early in the month the projection rests on little of the month’s own data. Use it directionally.
• Not accounting for one-time events. A data migration or load test spikes costs temporarily, and the linear model treats it as a trend shift. Once the spike passes, the forecast corrects itself.
• Ignoring the seasonal view. If your batch jobs run on weekdays only, compare the seasonal forecast with the linear one.

FAQ

Can I forecast at the tag level? Not yet. The Forecast page works at the organization and account level.

How much history does the model need? It uses up to 90 days. With little history the trend is less reliable, so treat the first weeks after connecting an account as directional.

Does the forecast account for reserved instances and savings plans? Yes. The forecast is based on your actual billed costs, which already reflect RI and SP discounts.

Can I export the forecast data? Not from the Forecast page. Ask Claude through the MCP server, whose get_cost_forecast tool returns the projection.

Key takeaways

• The forecast is most useful as an early warning: pair it with budget forecast alerts to catch overruns before they happen.
• Narrow to an account to find which part of your estate is driving an increase.
• Check the accuracy panel to judge how much to trust the projection for your workloads.