The Lab Notebook

By Regina Fernandez

Fun rating: 2/5

Difficulty rating: 3/5


What is the general purpose? The purpose of a laboratory notebook is to keep a permanent and detailed record of the materials, procedures, results obtained (data), and any observations made by a scientist during an experiment. 

Why do we use it? There are multiple reasons why scientists are required to have a lab notebook:

  1. To remember: No matter how much time has passed (one, three, or even 20 years), a scientist can always go back to their lab notebook and read the experimental details. For example, a scientist who wants to publish their findings in a scientific journal can refer to their lab notebook to write the materials and methods section. 
  2. To reproduce the experiment: Reproducibility is an important part of the scientific method. Any scientist should be able to reproduce the experiment and obtain similar results. Thus, a detailed lab notebook will allow other scientists to follow the procedure and confirm the results.   
  3. For protection: Scientists make discoveries that can be patented. The lab notebook is a legal document that serves as proof of the discovery.

Keeping a good lab notebook is an important practice for any scientist. Famous scientists like Alexander Graham Bell, who invented the telephone, spent time recording all of his findings in a lab notebook (Figure 1). Here, you are going to learn the basic guidelines for keeping a good lab notebook. 

Figure 1. Laboratory notebook of Alexander Graham Bell. Image

How does it work? The following are general guidelines that you can follow to keep a good lab notebook. These guidelines may change depending on the lab where you do your research.

Choose a lab notebook: The most common lab notebooks are the bound notebook and the electronic notebook. Each has its advantages and disadvantages. 

  • Bound notebook: 
    • Advantage: Hard to lose pages or falsify because most notebooks are numbered.
    • Disadvantage: Difficult to search for an experiment
  • Electronic notebook:
    • Advantage: Easy to search for an experiment
    • Disadvantage: Records have to be backed up frequently and can get corrupted (damaged).

Prepare the lab notebook:

  1. Write your name, institution, year, and name of the project on the cover or first page of the notebook. 
  2. If the lab notebook pages are not numbered, write the number on the top corner.
  3. Table of contents: Leave blank pages at the beginning of the notebook and label them as “TABLE OF CONTENTS”. Every time you do an experiment, you will update the table of contents with the name of the experiment, date, and page number. 

Information to record for each experiment:

  1. Date: If the experiment takes multiple days, include the date on each page.
  2. Descriptive title of the experiment: A descriptive title will make it easier to find the experiment in the table of contents. For example, you can write “Protein X levels in the brain” instead of “Experiment #3”.
  3. Objective and hypothesis of the experiment: Write the purpose of the experiment and your hypothesis. 
  4. Materials and chemicals: Include the name of all the chemicals and amounts that will be used during the experiment. Make sure to include your calculations. Also, write the name and brand of any equipment that will be used and make notes on how to use it.
  5. Procedure: Write a step-by-step protocol of what you are going to do.
  6. Observations: Write down EVERYTHING. Write any data obtained from each step of the process. Make a note if you adjust the protocol while doing the experiment or if you make a mistake. These notes will help you interpret your findings. If you have to repeat the experiment you can go back to the notes and determine whether you need to further adjust anything from the protocol. Also, observations are very important, especially if someone else wants to reproduce the experiment, so remember to write down every single detail of what happens during the experiment.
  7. Data analysis: Analyze your data. If special software is required, use the software to analyze the data, print out the results, and tape them on the notebook. Write the location of the file if you are not able to print out the analysis. 
  8. Conclusions: Summarize your results by writing a short description, and include future directions regarding how to proceed with your research. 
  9. Sign each page.

Other requirements:

  • Use black or blue permanent ink pens to prevent another person from erasing or editing your records. 
  • Handwriting should be clear so that anybody can read it.
  • If you make a mistake, cross out the mistake with a single line and write the correction next to it. For example: Hipotesis Hypothesis
  • Always be honest about what you write in your lab notebook.

Follow these basic steps to keep a good lab notebook, and ask your boss and labmates if there is additional information or specific requirements they would like you to add. Your lab notebook is your legacy, so make sure you keep a good record of the experiments you do! 

Figure 2. Laboratory notebook of a graduate student. Image

Edited by Jenna Beam and Catherine Lewis

Rating illustrations by Brooke Felsheim