Compare this period to the last one — period-over-period is built into every Simplytics dashboard
A single number — "12,400 visitors this month" — doesn't tell you much on its own. The question you actually have is "compared to what?" Is that up or down on last month? Better or worse than the same stretch a week ago? Simplytics now answers that on every dashboard: turn on vs previous period and each chart and metric gets its own before-and-after.
This is a short note on what the feature does, how it picks the comparison window, and the one delta we deliberately don't show — because showing it would mean making a number up.
What "vs previous period" does
Next to the date-range picker there's a vs previous period toggle. It's on by default and remembers your choice, so once it's set you don't touch it again.
Flip it on and two things happen:
- A dashed overlay appears on the visitors/views chart, plotting the immediately preceding window of the same length. Looking at the last 30 days? The dashed line is the 30 days before that. Looking at a single week? It's the week before. The comparison always matches the length of whatever range you've selected, so it's like-for-like.
- Delta badges appear on the metric boxes — Visitors, Views, Sessions, Bounce Rate and Views/Session — each showing the percentage change against that previous window. Up is green, down is red, with one deliberate exception: Bounce Rate is inverted, because a rising bounce rate is bad news, so it's coloured accordingly. If the previous period had zero of something, the badge reads "new" instead of a nonsense "+∞%".
It works for any range and any metric you switch the chart to — no separate report, no configuration.
The one number we won't fake: Average Duration
Look closely and you'll notice one metric box has no delta badge at all: Average Duration. That's not an oversight. It's the most honest thing about the whole feature.
To show you "avg. session duration, this period vs last," we'd need the previous period's session durations. But Simplytics deletes raw visit records every night — that's the core of how it stays cookie-less and stores no personal data. Once a day closes, the individual sessions that would let us recompute an average duration for some earlier window are gone. We keep aggregates forever; we don't keep the raw material a retroactive duration delta would require.
Plenty of tools would happily print a number there anyway, reconstructed from whatever's lying around. We'd rather show nothing than show a figure we can't stand behind. Every other delta on the dashboard is computed from daily aggregates we genuinely have; the duration delta isn't, so it doesn't exist. It's the same trade-off that lets us keep your history forever because we threw the raw data away — we've written about that trade-off in full.
Why this is here at all
Period comparison is table stakes in analytics — GA4, Plausible and the rest all do a version of it. The point isn't that it's novel; it's that you get it as part of a cookie-less, no-consent-banner dashboard for $1/month, alongside funnels, country maps, custom events and CSV export, with your data kept in the EU. That's the whole positioning: a lot of the functionality of the $9–15/month tools, honestly built, for a dollar. If you're weighing it up, the Simplytics vs Google Analytics page has the side-by-side.
If you already have a dashboard, the toggle is waiting next to your date picker. If you don't, start a 30-day trial — no card — and it'll be on by default when your first numbers land.