How to Write a Lab Report

Girls conducting science experiment and taking notes.

Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels.

Updated on July 21, 2024

Lab reports are an essential part of all laboratory courses and usually a significant part of your grade. If your instructor gives you an outline for how to write a lab report, use that. Some instructors require a lab report to be included in a lab notebook, while others will request a separate report. Here's how to write a lab report you can use if you aren't sure what to write or need an explanation of what to include in the different parts of the report.

Lab Report

A lab report is how you explain what you did in ​your experiment, what you learned, and what the results meant.

Lab Report Essentials

Title Page

Not all lab reports have title pages, but if your instructor wants one, it would be a single page that states:​

Title

The title says what you did. It should be brief (aim for ten words or less) and describe the main point of the experiment or investigation. An example of a title would be: "Effects of Ultraviolet Light on Borax Crystal Growth Rate". If you can, begin your title using a keyword rather than an article like "The" or "A".

Introduction or Purpose

Usually, the introduction is one paragraph that explains the objectives or purpose of the lab. In one sentence, state the hypothesis. Sometimes an introduction may contain background information, briefly summarize how the experiment was performed, state the findings of the experiment, and list the conclusions of the investigation. Even if you don't write a whole introduction, you need to state the purpose of the experiment, or why you did it. This would be where you state your hypothesis.

Materials

List everything needed to complete your experiment.

Methods

Describe the steps you completed during your investigation. This is your procedure. Be sufficiently detailed so that anyone can read this section and duplicate your experiment. Write it as if you were giving directions for someone else to do the lab. It may be helpful to provide a figure to diagram your experimental setup.

Data

Numerical data obtained from your procedure usually presented as a table. Data encompasses what you recorded when you conducted the experiment. It's just the facts, not any interpretation of what they mean.

Results

Describe in words what the data means. Sometimes the Results section is combined with the Discussion.

Discussion or Analysis

The Data section contains numbers; the Analysis section contains any calculations you made based on those numbers. This is where you interpret the data and determine whether or not a hypothesis was accepted. This is also where you would discuss any mistakes you might have made while conducting the investigation. You may wish to describe ways the study might have been improved.

Conclusions

Most of the time the conclusion is a single paragraph that sums up what happened in the experiment, whether your hypothesis was accepted or rejected, and what this means.

Figures and Graphs

Graphs and figures must both be labeled with a descriptive title. Label the axes on a graph, being sure to include units of measurement. The independent variable is on the X-axis, and the dependent variable (the one you are measuring) is on the Y-axis. Be sure to refer to figures and graphs in the text of your report: the first figure is Figure 1, the second figure is Figure 2, etc.

References

If your research was based on someone else's work or if you cited facts that require documentation, then you should list these references.

Cite this Article Your Citation

Helmenstine, Anne Marie, Ph.D. "How to Write a Lab Report." ThoughtCo, Jul. 21, 2024, thoughtco.com/how-to-write-a-lab-report-606052. Helmenstine, Anne Marie, Ph.D. (2024, July 21). How to Write a Lab Report. Retrieved from https://www.thoughtco.com/how-to-write-a-lab-report-606052 Helmenstine, Anne Marie, Ph.D. "How to Write a Lab Report." ThoughtCo. https://www.thoughtco.com/how-to-write-a-lab-report-606052 (accessed September 9, 2024).

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