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20 free and open source data visualization tools

20 free and open source data visualization tools

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Tharika Tellicherry
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February 21, 2018
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3 min read
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Data visualization is helping companies worldwide to identify patterns, predict outcomes, and improve business returns. Visualization is an important aspect of data analysis. Simply put, data visualization conveys outcomes of tabular or spatial data in a visual format. Images have the power to capture attention and convey ideas clearly. This aids decision making and drives action for improvements.

With the use of the right tools, you can sketch a convincing visual story from your raw data. Here are some free and open source tools for data visualization:

1) Candela

If you know Javascript, then you can use this open source tool to make rich data visualizations. Candela is an open-source suite of interoperable web visualization components.

Candela
Candela

2) Charted

Charted is a free data visualization tool that lets you create line graphs or bar charts from CSV files and Google spreadsheets. The toll comes with integrated components including LineUp component, UpSet component, OnSet component, Vega visualizations, and GeoJS geospatial visualizations. The tool does not store the data or manipulate it. Focused purely on visualization, it comes with basic features to create a line or stacked charts with labels and notes.

Charted
Charted

3) Datawrapper

Datawrapper is a mobile-friendly data visualization tool that lets you create charts and reports in seconds. The free version of the tool meant for a single user supports 10,000 monthly chart views. Using the tool, you can create different types of visualization such as bar chart, split chart, stacked chart, dot plot, arrow plot, area chart, scatter plot, symbol map, and choropleth map. You don’t need coding or designing skills to use the tool.

Datawrapper
Datawrapper

4) Google Data Studio

Google’s data visualization tool is free and easy to set up if you have a Gmail account. You can connect it easily with Google products such as Google AdWords, Google Analytics, YouTube Analytics, and Google Sheets.

Google Data Studio
Google Data Studio

5) Google Charts

Another simple and free data visualization tool by Google is the Google chart tool. The tool comes with interactive charts and data tools for visualization.

Google Charts
Google Charts

6) Leaflet

The leaflet is an open-source JavaScript library that allows you to make mobile-friendly interactive maps. The tool has a lot of plugins for adding features and works well on various desktop and mobile platforms.

Leaflet
Leaflet

7) MyHeatMap

MyHeatMap is a free tool to view your geographic data interactively. The free version of the tool offers only public maps and you can add only 20 data points for each of those free maps. The tool makes it easy to understand the data with color-coded heat maps. You can also switch between data sets within the same map.

MyHeatMap
MyHeatMap

8) Openheatmap

This free tool lets you turn your spreadsheet into a map. You can upload your CSV file or Google sheet to create an interactive online map in seconds. The tool can be used to explain data like customer demographics by zip codes.

Openheatmap
Openheatmap

9) Palladio

Palladio is a free tool designed to visualize complex historical data. It comes with features like map view, graph view, list view and gallery view. You can use the tool to visualize data in CSV, TAB, or TSV files. With the graph view, you can visualize the relationship between dimensions of your data. The data is displayed as nodes connected by lines. The list view, on the other hand, allows you to arrange data to make customized lists. The tool also has a gallery view to display data within a grid.

Palladio
Palladio

10) RawGraphs

RawGraphs is an open-source platform that helps you visualize TSV, CSV, DSV, or JSON data. The free tool is simple to use and helps in converting data to charts.

RawGraphs
RawGraphs

11) Tableau Public

Tableau Public is a free business intelligence tool that allows users to create and share interactive charts, graphs, maps, and app. The free version of the tool comes with 10 GB of storage. You can connect it to data sources like Google Sheets, Microsoft Excel, Text files, JSON files, Spatial files, Web Data Connectors, OData, and statistical files such as SAS (*.sas7bdat), SPSS (*.sav), and R (*.rdata, *.rda).

Tableau Public
Tableau Public

12) Timeline

A timeline is a free tool that allows you to create timelines for reports. You can connect your Google Drive account to create a timeline from Google Spreadsheet using the templates given in the tool. Using JSON, you can create custom installations.

Timeline
Timeline

13) Chartist.js

Chartist.js is a free data visualization that allows you to create responsive charts fast and easy.
The tool offers great flexibility and is customizable. You can even use CSS animations and transitions to your SVG elements.

Chartist.js
Chartist.js

14) ColorBrewer

ColorBrewer is a free tool that can be used to make your maps better in terms of color schemes. The tool makes it easy to differentiate colors on a complex map.

ColorBrewer
ColorBrewer

15) D3.JS

D3.JS is a free JavaScript library that helps you create images using data. The tool enables you to connect arbitrary data to a Document Object Model (DOM), and then apply data-driven transformations to the document. With DOM programming API, programmers can access documents as objects.

D3.JS
D3.JS

16) Plotly

Plotly is an open-source tool that allows you to compose, edit and share interactive data visualizations. You can use the tool to create D3.js charts and maps by uploading CSV files or connecting to the SQL database. You can also create charts with R or Python.

Plotly
Plotly

17) Polymaps

Polymaps is a free javascript library for creating dynamic, interactive maps in browsers. You can use the tool to get a display of multi-zoom datasets over maps. The tool uses scalable vector graphics (SVG) to display images, thus enabling you to define the design using CSS.

Polymaps
Polymaps

18) Weave

The Weave is a free data visualization platform that is ADA-compliant. The tool comes with a full keyboard and assistive device navigation and complete screen reader support. The tool also automatically gives descriptions of the images in real time.

Weave
Weave

19) Dygraphs

Dygraphs is an open-source charting library based on JavaScript. This free tool can be used to analyze dense data sets. The tool is highly customizable and works well in all browsers. The tool offers strong support for error bars/ confidence intervals.

Dygraphs

20) GanttPro

Apart from these, there are many data visualization tools that offer a free trial for a limited time GanttPro, a project management tool, for instance, helps you create charts for projects for free during their 15-day trial period.

GanttPro
GanttPro

Data visualization is crucial for accurate data analysis. With the right tools in hand, you can easily summarize and explain complex data to your stakeholders. By leveraging actionable insights generated from data, companies can make big profits and savings. Just how big are we talking about? Netflix saved around $1 billion in 2017 with its ML algorithm that recommends personalized TV shows and movies to subscribers. When used right, data analysis and visualization have the power to change the way people live their lives.

Know a great open source tool for data visualization? Share it in comments below.

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February 21, 2018
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Assess the Skills That Truly Matter

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How would you design an API for a payment gateway?

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