How to read graphs and diagrams

Thursday, May 23, 2024
by Navya Vikraman Nair, Peer Success Coach and PhD Candidate in Environmental Science

Are you looking to feel more confident reading and understanding graphs and diagrams? You’ve come to the right place.  

No matter what field you study, you will need to read and analyze graphs and diagrams. It's an essential skill for understanding complex concepts and drawing meaningful conclusions.  

Understanding graphs and diagrams 

Determine what the graph is measuring. 

  1. Read the title and labels to understand what is represented in the graph. The title of the graph provides context for the information presented. The labels on the axes (x-axis and y-axis) tell you what variables are being measured and the units of measurement. 
  2. Check the scale or increments of measurement on the axes to interpret the data accurately. For example, if the scale on the y-axis of a graph representing temperatures ranges from 0°C to 100°C, you'll know that each increment represents a temperature increase of 10°C. 
  3. Consider the context and background information provided alongside the graph or diagram to interpret it correctly. For example, you may consider climate change and human activity if you're analyzing a graph on global temperature trends. 

Analyze patterns and trends 

Identify key elements that convey information to analyze and recognizing trends, patterns, outliers or clusters in graphs and diagrams. Consider the following elements for different graphs.

  • Line graphs: identify the direction and slope of lines to understand trends. An upward slope indicates an increase, a downward slope indicates a decrease, and a steady slope suggests stability. 

  • Bar graphs: compare the heights of bars to identify differences and similarities between categories. Look for variations in bar heights to discern patterns. 

  • Scatterplots: examine the distribution of data points to discern correlations or associations between variables. Clusters of data points may indicate a strong relationship between variables. Scattered points may suggest a weak relationship or no relationship at all. 

  • Pie charts: compare the size of segments to understand the proportion of each category relative to the whole. Larger segments represent a larger proportion of the total data. 

Extract information 

Once you've analyzed the graph or diagram, you can extract valuable information to support your arguments or conclusions for essays or reports. Some ways to include this information are: 

  • Use data points or values to provide evidence for your claims. 

  • Summarize key insights or takeaways that the graph or diagram conveys. 

  • Calculate averages, percentages or rates based on the information presented to provide additional insights.  

  • Consider how the information presented relates to the broader topic or concept you're studying. Reflect on the trends and patterns you've identified to contribute to a deeper understanding of the subject matter. 


Do you need help deciding on what type of graph or diagram to create for an assignment? Read determine the best way to graph your data

Don’t hesitate to reach out to your instructors and TAs for help reading graphs and diagrams. You can also book an appointment with a Peer Success Coach to work on these skills.