Is that jump in your conversion rate real, or just luck?

Your signup page has converted at 3.4% for months. Last week it hit 4.86%, which is 34 signups from 700 visitors, and the team wants to ship the change. This template asks the only question that settles it: how often would a page that never changed produce a swing that big?

Marketing Intermediate Statistics free

After you install, this is the model to open.

Is That Rate Real, or Just Luck?

  1. In your spreadsheet, click the Sortia icon in the strip of icons down the right-hand edge. No strip? Click the arrow at the bottom-right to open it. You can also use Extensions, then Sortia, then Open Sortia.
  2. Click Start from a template and put that name in the search box.
  3. Pick the card with that name and click Load this template. It arrives on a new tab with real numbers already in it.

The answer

One click runs a chi-square goodness-of-fit test on the two counts. Here is what comes back.

Observed signup rate
4.86% 34 of 700 visitors
Lift vs the 3.4% baseline
+42.9% 1.46 percentage points
P-value, two sided
0.033 chi-square 4.53, 1 df
Pure chance fakes this
1 in 30 unchanged pages tested

The rate went from 3.4% to 4.86%, a +42.9% relative lift that looks like an obvious win. The test agrees it is probably real, but the margin is thin: p = 0.033 clears the 5% bar and would fail a stricter 1% one, and a page that never changed would swing this far about 1 time in 30. The entire verdict rests on roughly 10 extra signups, the gap between the 34 you saw and the 23.8 the baseline predicts. Take away one signup, 33 instead of 34, and p becomes 0.055 and the answer flips to noise.

The model

Two counts and the baseline rate you are testing against. That is the whole model.

Visitors in the test700
Signed up34 (4.86%)
Did not sign up666
Baseline rate to beat3.4%
Signups the baseline predicts23.8
Significance bar5% (p < 0.05)

Once it is in your sheet

  1. The model arrives with real numbers in it and runs as it stands, so you can press the button first and understand it second.
  2. Change the numbers to yours. The sheet marks which cells are inputs and which hold formulas, and most labels carry a note explaining the row.
  3. Press the run button at the bottom of the panel. It is labeled for the tool you are in, and the result lands on its own tab, with a written reading of it beside the figures.

Never used Google Sheets? Start here goes the whole way, in seven steps, and assumes nothing.