Lab Report Structure Guide
Build an IMRaD lab report skeleton with word budgets per section, a what-goes-where checklist and a percent error calculator.
About this tool
Lab Report Structure Guide
Build an IMRaD lab report skeleton with word budgets per section, a what-goes-where checklist and a percent error calculator.
A lab report structure guide lays out the IMRaD skeleton — Introduction, Methods, Results and Discussion — and assigns each section a word budget, a grammatical tense and a checklist of what a marker expects to find there. It also runs the two calculations a results section always needs: percent error, (measured − accepted) ÷ accepted × 100, and percent difference when there is no accepted value. Written for school practicals, undergraduate lab courses and formal journal-shaped reports, with the abstract capped at the 250-word APA ceiling most rubrics reuse.
How to use Lab Report Structure Guide
- 1
Open Lab Report Structure Guide on AltFTool — it loads instantly in your browser.
- 2
Choose a "Report style" - School practical write-up, Undergraduate lab report or Formal IMRaD report - and set the "Word target" anywhere from 300 to 8,000 words.
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Work down the "Section skeleton", ticking each section as you draft it; every card carries its own word budget and the checklist of what a marker looks for there.
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Enter "Your measured value" and the "Accepted / literature value" for the percent error headline, with signed percent error, absolute error and percent difference beneath it; "Copy skeleton" copies the whole plan.
Why use Lab Report Structure Guide
Section-by-section checklist
Each section lists what a marker looks for, so nothing is left to guesswork.
Word budgets that add up
Allocations sum exactly to your target and give the discussion the largest share.
Error maths built in
Percent error and percent difference are calculated from your own numbers, with divide-by-zero handled.
Common use cases
- Split a 1,500-word undergraduate report so the discussion gets 450 words instead of the 80 that are left at 2 a.m.
- Check whether a measured value of 9.62 m/s² against the accepted 9.81 m/s² is a 2% error or a 20% one before writing the discussion.
- Give a school student a tick-list of what belongs in Method versus Results so the two stop blurring together.
- Convert a finished experiment into a journal-shaped IMRaD outline before drafting a project report.
Frequently asked questions
What is the IMRaD structure of a lab report?
IMRaD stands for Introduction, Methods, Results and Discussion — the standard order for reporting original experimental work. The introduction says why the experiment was done, methods says how, results says what happened, and discussion says what it means; abstract, references and appendices sit around that core.
How do you calculate percent error in a lab report?
Percent error = (measured value − accepted value) ÷ accepted value × 100. Measuring g as 9.62 m/s² against the accepted 9.81 m/s² gives −1.94%, a result 1.94% below the accepted value. If there is no accepted value, use percent difference: |a − b| ÷ ((a + b) ÷ 2) × 100.
How long should a lab report abstract be?
Aim for 150-250 words. APA 7th edition recommends that range and most course rubrics and journals reuse the 250-word ceiling, so an abstract does not get longer just because the report does.
What tense should a lab report be written in?
Methods and results go in the past tense, usually passive — the solution was heated, the mass was recorded — because they describe what was done on one occasion. Established theory and your interpretation in the discussion go in the present tense, because they are claims about how things are.