How to Write a Lab Report: Complete Guide

Jul 15, 2019

Jul 15, 2019 | Guide

While training to be a scientist, it is important to know how to write a lab procedure and to be able to write effectively so that you can explain the details of your experiment clearly and explicitly.

Throughout your time at the university, you’ll be asked to prepare laboratory reports for several of your laboratory classes.

Below are the guidelines for writing a scientific laboratory report. Additionally, laboratory reports are written in past tense and the third person. And always remember that grammar and spelling are important.

Assignment to Write a Lab report is common in science subjects and courses.

In fact, these reports account for 25% of science courses.

That is a significant percentage, yet students do not pay enough attention when writing lab reports.

How to Write a Lab Report

Another problem is lab reports do not have standard requirements; different teachers have different expectations from their students’ lab reports.

All lab reports serve the same purpose, which is to report the experiment’s findings and explain the importance of the findings.

All lab reports have key elements such as data, a list of materials, and the hypothesis.

You will only write a good lab report after understanding all the essential elements you have to include.

If you know the structure, you can write a lab report to match the requirements and expectations of your professor.

Requirements of Lab Reports

Requirements of Lab Reports

A lab report should:

  • Clearly, present data from the experiment.
  • Show your understanding of the concept behind the data.
  • Explain why and how any variances happened.
  • Explain why the variances affected the experiment.
  • Present your understanding of the concept the research was supposed to examine.

The point is, it is not enough to understand the format of a lab report: You have to organize your ideas and thoughts carefully and coherently.

Structure of a lab report

The format you use for your lab report should take into account the instructions from your instructor.

However, generally, a lab report has the following sections:


  • precisely identifies the focus of the lab


  • provides an overview of the report content, including findings and conclusions
  • usually, the last part of the document to be written
  • may not be required in a short lab report


  • provides appropriate background to the experiment and briefly explains any relevant theories
  • states the problem and/or hypothesis and
  • concisely states the objective/s of the experiment


  • describes equipment, materials, and procedure(s) used
  • may include flow charts of procedures and/or diagrams of the experimental set-up
  • outlines any processing or calculations performed on the collected data (if applicable)

Results and Analysis

  • presents results of the experiment graphically or by using tables. Figures often include error bars where applicable
  • discusses how results were analyzed, including error analysis


  • interprets key results about the aims/research question
  • summarises key findings and limitations
  • makes recommendations to overcome limitations and indicate future directions in research


  • reminds the reader what problem was being investigated
  • summarises the findings of the problem/hypothesis
  • briefly identifies big-picture implications of the findings (Answers the question “So What?”)


  • lists the publication details of all sources cited in the text, allowing readers to locate sources quickly and easily
  • usually follows a specific referencing style


  • an appendix (plural = appendices) contains material that is too detailed to include in the main report, such as tables of raw data or detailed calculations


Lab report title page

The title tells the reader the focus of the experiment.

The title is a brief way of telling the reader what the experiment is about and what the report includes.

It may or may not indicate the conclusion.

The following is an example of a good lab report title:

An experiment to determine the chemical equilibrium using Le Chatellier’s Principle.

In your title, be precise (avoid wordiness) and do not use abbreviations.

The title normally appears on the title page.

But, some instructors will tell you not to include a title page.

If the page is a requirement, it should be a single page with the following information:

  • The name (title) of the experiment.
  • Your name and the name of other students you experimented with.
  • The instructor’s name.
  • The date.

Of course, the title page structure might be determined by the academic paper format specified.

However, do not include the page if it is not included in the instructions.


lab report abstract

An abstract is a summary of the report.

The length of the abstract should be 10% of the whole report.

Therefore, a 500-word lab report should have an abstract of about 50 words.

Still, an abstract should not exceed 250 words or one page.

The abstract should contain the results, your interpretation, and a brief explanation of the methods.

From the abstract, your reader should tell what the report is all about and if it is relevant to their own research.

The abstract should be just one paragraph; therefore, it should not be detailed or contain too many technical terms.

In simpler terms, an abstract is the short version of your lab report.


lab report abstract

The introduction of a lab report serves to inform the reader of the relevance of the experiment.

Therefore, the first thing you do in your introduction is background information relating to the experiment.

You are providing this background information so that the reader can understand the hypothesis.

Sometimes this section may contain background information, briefly summarize how the experiment was performed, state the experiment’s findings, and list the investigation’s conclusions. Even if you don’t write a whole introductory section, you need to state the purpose of the experiment or why you did it. This would be where you state your hypothesis.

A hypothesis is an answer your experiment offers.

An example of a hypothesis is: Temperature affects the rate of diffusion.

To have an easier time creating a hypothesis, ask yourself how the theory you are trying to prove connects to your experiment.

Also, in the introduction, show how your experiment solves real-world problems.

As much as you should include all relevant background information, do not get carried away and state the experiment results and the materials and methods used.

Materials and methods

In this section, list the materials used.

Then, outline the methods used to gather the data clearly and chronologically.

The idea is to help the reader understand how the experiment was conducted.

However, do not provide a step-by-step experiment process; that information is included in the lab manual.

Include information about any special apparatus or techniques used in the experiment.

Do not be too detailed or copy the experiment procedure from the lab manual.

During the lab, take detailed notes on procedures and results and note any differences in procedures or expected outcomes. Record enough detail to allow someone else to repeat the experiment based on your notes.


Under the results section, summarize your data.

Your results should appear in a logical and chronological order.

You can present your data in tables and graphs.

The important thing is to label everything correctly and clearly, indicating all the measuring units.

There are two different kinds of data you should record; quantitative and qualitative.

Quantitative data is observable and measurable in units such as grams, millimeters, and degrees.

On the other hand, qualitative data is unmeasurable observable data.

It includes things you observe with your senses, such as smell and color.

Do not discuss if the results were what you expected or compare your results with those of other researchers.


The discussion is an essential section of the lab report as it demonstrates your ability to interpret the data and results of the experiment.

It would help if you discussed whether or not the results support your hypothesis.

In this section, you also compare your work to those of other scientists: Were your results consistent with those of other scientists?

However, do not discuss human errors.

Therefore, do not report that you accidentally used the wrong chemical at some point in your experiment.


When providing background information in your introduction or supporting your results in the discussion, you may have to cite works of other scientists or refer to your lab manual.

You should properly cite all external sources, and you will include these citations under the references section.

The academic referencing style specified will determine the format of the citations.

Most instructors prefer APA and CSE for lab reports.

However, do not assume; confirm with your professor the formatting style required.

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


In conclusion, write what you learned from the experiment.

Discuss the lesson learned regardless of whether the results supported your hypothesis or not.

The point is to demonstrate to the reader that the experiment was successful.

So, instead of summarizing the results, explain the meaning of the results.


An appendix is a piece of information that does not have to be included in the lab report but could help a reader who wants to learn more about the experiment or the theory the experiment attempted to prove.

The use of appendices helps to unclutter the lab report.

Note that if you include appendices, you should refer to them in the lab report.

Things that you can include in the appendices section include:

  • Photographs of the experiment, which may help the reader better understand the findings.
  • Calculations that provide a better understanding of the methodology section.
  • The raw data from the lab
  • Data tables that are not crucial to the discussion in the lab of the results but may be helpful to the reader as a reference

Each unique item should be a separate appendix.

Additional tips on how to write a lab report

  • Proofread your paper at least two times. When proofreading, check the flow of the content and confirm you have followed all the instructions.
  • Check that there is no plagiarism. Plagiarism is more than copying material word for word; it also uses someone else ‘s ideas or phraseology without referencing the other work or another person.
  • Use the past tense when discussing methodology and findings.


A lab report provides useful information about an experiment.

It is an important assignment that contributes a significant percentage to your grade.

All you have to do to write a lab report excellently is to follow the format and tips discussed above and the instructions from your teacher.