DaylytixA performance budget is a limit you set for a site’s speed. When a scheduled audit finds the site over a limit, Daylytix sends an alert, so a slow release doesn’t go unnoticed until a client complains.
Budgets belong to a monitor (a scheduled audit). A site without a monitor is not checked against budgets. See Scheduling audits.
The four budgets
| Budget | Alert when | Unit |
|---|---|---|
| LCP | Largest Contentful Paint is at or above the value | milliseconds (lab measurement) |
| CLS | Cumulative Layout Shift is at or above the value | score, for example 0.1 |
| Mobile score | The PageSpeed mobile score is at or below the value | 0-100 |
| Desktop score | The PageSpeed desktop score is at or below the value | 0-100 |
A value of 0 turns that budget off. Set one, all four, or none.
Setting budgets
- Open Monitoring → Scheduled Audits.
- Add a monitor, or edit an existing one.
- In Performance Budget Alerts, fill in the limits you want - for example LCP 2500, CLS 0.1, mobile score 50.
- Fill in Alert email and/or Slack Webhook URL so the alerts reach you.
- Click Save Monitor.
Choosing values
Google’s own Core Web Vitals thresholds are a good starting point: LCP of 2.5 seconds (2500 ms) or less and CLS of 0.1 or less count as good. PageSpeed Insights treats a score of 90 or more as good and below 50 as poor. Rather than aiming for perfection, set the budget just below what the site achieves today - then an alert means something got worse.
Lab values move between runs. PageSpeed scores vary a few points from run to run. Leave a margin, or you will get alerts for normal noise.
How alerts are sent
After each scheduled run, Daylytix compares the results with your budgets. For every budget that is crossed:
- an entry is added to Monitoring → Alert Center;
- one combined email goes to the monitor’s Alert email, listing each crossed budget with the measured value and the limit, plus the current and previous score;
- the same alert is posted to Slack if you set a webhook.
Alert emails are sent through your own mail server, so add your SMTP settings in App Settings → Notifications. See Automated email reports.
Testing a budget
To check that alerts reach you, set a budget the site is sure to cross - for example a mobile score of 99 - and click ▶ Run on the monitor. When the run finishes, you should see the alert in Alert Center and in your inbox or Slack. Then set the budget back to a real value.