Your school marks every IA in the cohort, the IB re-marks a sample, and if the school's marking is out of line the whole cohort's marks move. The number on your transcript can therefore be one neither your teacher wrote nor anyone explained. Grade boundaries found online apply to the moderated mark.
The IA mark you are planning with is not the one you will get
Your teacher marks your Internal Assessment. The IB then moderates it, and the number that reaches your transcript can be neither the one your teacher wrote nor one anybody explained to you.
What actually happens to your mark
Your school marks every IA in the cohort and submits those marks to the IB. The IB then requests a sample of the marked work, chosen to span the school's mark range rather than at random, and sends it to a certified examiner. That examiner marks the sample independently.
The two sets of marks are then compared statistically. If the school has marked consistently differently from the IB standard, an adjustment is applied. That adjustment reaches every candidate at that school for that component, sampled or not. Your mark can move because of how your teacher marked somebody else.
It moves in both directions. A school that marked conservatively can see its whole cohort lifted. The ideal outcome, and a common one, is that the school is already in line and nothing changes at all. Moderation is a calibration of your teacher, not a re-marking of you.
Why this matters for the grade boundaries you found online
Somewhere in a spreadsheet or a forum thread you have seen a table saying you need, for example, a certain total for a 7 in your subject. Two things about that table are worth knowing before you plan around it.
The boundary is applied to your moderated total. The IA component of that total is the post-moderation figure, not the mark your teacher handed back with a smiley face in the margin. If you are sitting one mark above a boundary on your teacher's numbers, you are not safely above it.
Boundaries are set per session. They are fixed after that session's examinations, against that session's papers and cohort. Last year's boundary is a reasonable guide and a bad guarantee. Planning to land exactly on a boundary you read somewhere is planning to be rounded down by something you cannot see.
What follows from this
The practical consequence is not "panic". It is that marks you can defend on the page are worth more than marks your teacher is willing to give you. A moderator has never met you, was not in the lab, and is working only from the document. Everything your teacher filled in from memory, that you did control the temperature and that you did understand why the anomaly happened, has to be visible in the text, or it is not there at all.
That is also why a second reader is worth anything. Your supervisor knows what you meant. A reader who has only the page, like the moderator, sees what is there.
Read as a stranger would read it
Send your draft and get every criterion scored and every lost mark explained by someone who has never met you. Comments in the margin of a copy.
Sources
Moderation process and the application of an adjustment factor to a whole cohort: IB, Assessment principles and practices: a guide for teachers and coordinators, and the IB's published description of internal assessment moderation. Checked 25 August 2026. Grade boundaries are set per session after examination; confirm any figure against your own subject's published boundaries rather than a third-party table. We do not reproduce IB assessment criteria here. Those are in your subject guide, which your coordinator can give you.