Skip to main content

PhantomJS / PhantomCSS VS. Diffy
for visual regression testing

PhantomJS is a headless browser. You can use it for visual regression testing with some custom work.
Diffy on the other hand is a SaaS platform where you can start right away.

14 days free trial period,
no credit card required

PhantomJS is deprecated. Meet Puppeteer

For a long time PhantomJS was the only scriptable headless browser. But after puppeteer came out PhantomJS became deprecated. We have used PhantomJS in early days but because of the memory and rendering problems switched over to Puppeteer.

Fewer False Positives

Spend less time reviewing your reports.

Diffy has custom intelligent image comparison algorithm that recognizes vertical shifts. PhantomCSS uses pixel perfect imagemagick.

No need to install and maintain your infrastructure

Start faster and save time waiting for reports

With PhantomCSS you'll need to install tool locally and you are limited by your computer's resources. With Diffy you start immediately on highly scalable infrastructure based on AWS Lambda.

No coding required

With PhantomCSS you'll need to learn CasperJS commands and build the script to take screenshots of your pages. Diffy allows simply upload list of URLs and start getting reports in 5 minutes.

Fabulous User Interface

Review reports in more convenient way

We have spent a lot of time refining our UI for large number of screenshots. Diffy has a thumbnails view and detail view with zooming option. PhantomCSS generates diffs and does not provide any UI to review them.

Diffy UI

14 days free trial period,
no credit card required

CI integration, sharing reports, notifications

Better collaboration with your team members and clients

Diffy has CLI tool and rich REST API that make CI integration like a breeze. Also, you don't need to worry about where to store results -- your team can go to the app and do the review. There are shareable report links so your team members or clients don't even need accounts in Diffy to see them. Diffy can post results to SLACK and send notifications by email. In case of BackstopJS you will need to take care of all these on your own.

Multiple environments, history

Review your historical data easily

PhantomCSS by default allows you to take screenshots and compare them with the baseline. While Diffy also can do that, it provides you with possibility to have multiple environments and keep the history of screenshots and comparison reports.

14 days free trial period,
no credit card required

14 days free trial period,
no credit card required

Latest from out Blog

7 min

25 Web Dev & QA Testing Statistics Every Developer Should Know [2022]

Trends move quickly in the web development and QA testing space. These trends can help predict where the QA and testing industry is headed. Development teams can adapt emerging best practices and methodologies while gaining a better understanding of the challenges they face throughout the development cycle.


7 min

Regression Testing: Your Step-by-Step Action Plan

Regression testing can be an overwhelming task. You can try to do too much and fail because of a lack of resources. In this article we will talk about how you can start with small practical steps to get results fast. Once you set up basic tests like visual regression testing you can start with more complex implementations including automation.
4 mins

Top Visual Regressions that You Can Spot with and without Automated Testing

Visual bugs are typically considered easy to spot. You can often see what’s missing or what’s amiss on a web page.

A photo that’s too much to the left, the wrong fonts, a missing button -- these are things that you can spot at a simple glance. But not all visual bugs are that easy to catch, especially not with the naked (or untrained eye).

This is where automated visual regression tools like Diffy come into play. They can help you spot elusive visual bugs easily, even if you have to test hundreds of pages.