How your IELTS band score is calculated: rounding rules, raw marks and half-bands

The overall band is the arithmetic mean of your four skill bands, rounded to the nearest half band — and the rounding is generous: an average ending in .25 rounds up to the next half, and .75 rounds up to the next whole band. That one rule creates most of the "how did they get that number" confusion, and, more usefully, it creates arithmetic you can plan around.

The rounding in practice

• L 6.5, R 6.5, W 6.0, S 6.0 → average 6.25 → overall 6.5
• L 7.0, R 7.0, W 6.5, S 6.5 → average 6.75 → overall 7.0
• L 8.0, R 7.5, W 6.5, S 7.0 → average 7.25 → overall 7.5
• L 6.5, R 6.0, W 6.0, S 6.0 → average 6.125 → overall 6.0 (only .25 and .75 round up; 6.125 is nearer 6.0)

The planning consequence: an overall 7.0 does not require four 7.0s. Two 7.0s and two 6.5s gets there, as does 7.5 + 7.0 + 6.5 + 6.5. If Writing is your stubborn skill — it usually is — a half-band surplus in Listening or Reading buys the same overall for far less effort. Know which combination you are actually chasing before you allocate practice time; "everything to 7" is usually the most expensive route to the number on your certificate.

The caveat: institutions and immigration routes frequently set per-skill minimums alongside the overall, and those ignore your average entirely. Read your target's requirement precisely — "overall 7.0" and "overall 7.0 with no skill below 6.5" are very different preparation problems, and finding the requirement that actually binds you is a twenty-minute job worth doing first.

Where the four skill bands come from

Listening and Reading are raw-mark conversions: 40 questions each, one mark per question, no penalty for wrong answers, converted to a band by a table — set out with per-band targets in how raw marks become band scores. The published guide values: in Listening, ~16 correct ≈ band 5, 23 ≈ 6, 30 ≈ 7, 35 ≈ 8. Academic Reading runs about the same at the top (30 ≈ 7, 35 ≈ 8) but General Training Reading demands more raw marks for the same band — its texts are easier, so the table compensates. Exact boundaries shift a little between test versions to keep difficulty fair, but the planning math holds: band 7 means roughly 30 of 40 — you can leave ten marks on the table. Whole strategies follow from that: a guessed-under-time-pressure hard question costs nothing you can't afford, provided the easy marks are banked.

Writing and Speaking are criterion averages. Four criteria each, a whole band per criterion, averaged and rounded down to the half: criteria of 7, 7, 6, 6 average 6.5 → band 6.5; 7, 6, 6, 6 average 6.25 → band 6.0. The consequence: your lowest criterion is nearly always the binding constraint, and raising it by one band moves the skill more than polishing an already-strong criterion ever can. Feedback that names the weak criterion is therefore worth more than any general impression of an essay.

What this changes about preparation

1. Compute your cheapest overall. Write the four current bands, target overall, and find the half-band that is easiest to buy anywhere on the grid — respecting any per-skill floors your institution sets. If you do not yet know your Listening and Reading bands, a free Reading and Listening diagnostic measures both and breaks the result down by question type.
2. In L/R, chase raw marks, not perfection. The 7.0 candidate's job is 30/40: pacing that banks all the easy marks beats technique that rescues a few hard ones.
3. In W/S, chase your worst criterion. Ask of every practice session: which of the four numbers is this raising?
4. Half-band jumps are the unit of progress. Each half band in one skill moves the average by 0.125 — which, at a rounding boundary, is exactly the whole game. Averages of 6.75 and 6.625 print as 7.0 and 6.5 respectively; know when you are one boundary-crossing away.