The diagnostic
The diagnostic is the first measurement. Until you have taken it, the plan on Today is a sensible default rather than yours, and Progress has nothing to draw.
What it consists of
A trimmed version of the full mock — all four skills, chained, in one sitting, free on every plan:
| Part | What | Time |
|---|---|---|
| 1 | Two listening sections | ~5 min |
| 2 | Two reading passages | 40 min |
| 3 | A Task 2 essay | 40 min |
| 4 | A Parts 1–3 speaking interview | ~10 min |
You are asked for a target band and a test date first, if you have not already given them.
Each section is recorded as its own attempt linked to the sitting, which is why the result page shows them as one sitting and one overall band while Progress still counts each toward its own module.
Your result
Listening and Reading are marked the moment you submit them. Writing and Speaking go off to a language model, which takes up to a minute each, so the result page fills in those bands when they land. You can close the tab; the marking finishes without you.
The overall figure is the mean of the four. From it, Bandzen builds your study plan — and the plan is where the diagnostic actually pays off, because it knows which skills are behind and by how much.
Taking it more than once
Pro
Free includes 1 diagnostic. Retaking is a Pro feature. If you have already been measured, the page offers Retake with Pro and a link back to your last result, rather than letting you start one and stopping you at the end.
Retaking is not usually the useful move anyway. A second diagnostic measures the same skills the same way; ordinary practice attempts feed Progress and the plan just as well, within the 5 Reading and Listening tests Free includes.
Where it sits in Practice
"Sit a test" on the Practice hub lists the diagnostic alongside its section, duration, difficulty and whether you have taken it — next to the full four-skill mock test.