Categories: Firefox

The New Firefox: By the Numbers

There are 206 bones in the human body. Over 100 billion neurons in our brains (give or take a few after last weekend), and 35 trillion or so total cells. Nearly 8 billion people live on the planet, drinking 2.5 billion cups of coffee a day, and about 4 billion people are on the internet, looking at any one of the billion-plus websites now online.

The numbers behind Firefox Quantum

These are numbers colossal, unimaginable, and pretty darn incredible. And as we prepare to release the newest version of our Firefox browser, now affectionately known as the “new Firefox,” we thought it would be fun to give a rundown of some of the colossal numbers that went into this global undertaking by all of our engineers, volunteers, partners and staff.

Of course the answer to the universe is 42. But our gratitude comes down to two words: thank you!

We couldn’t do any of this without our loyal and rabid users who make us try harder, work later, code longer, cheer louder, and fight for more and more of what’s right in keeping the internet open, safe, and exciting.

Thank you, dear users, from all the bits and bytes and numbers and most importantly, for the one thing that can’t be measured and can’t be done without: the heart.

The New Firefox Quantum By the Numbers

How long did it take to make?

  • A full year. The project kicked off in 2016 and here we are.

How many lines of code were touched?

  • 75,342 files changed
  • 4,888,199 lines were added
  • 6,886,199 lines were changed

How many web extensions and compatible add-ons are available?

  • 6,000 listed web extensions on AMO
  • Over 70% of add-on users already have at least one installed

How many responsiveness and performance bugs were fixed?

  • We triaged 369 bugs targeted specifically at performance and responsiveness.

How many bugs were filed and fixed for the user experience?

  • For the user experience, we filed and fixed 1,190 software bugs.

How many authors contributed code?

  • More than 700 authors contributed code to Firefox since the August 6th release.

How many volunteers contributed to code development?

  • 80 contributors from all over the world, with nearly every time-zone represented in round-the-clock awesomeness!

How many ways can you customize the toolbar in the new Firefox?

  • There are 265,252,859,191,742,656,903,069,040,640,000* more ways to customize the new Firefox toolbar right out of the box!

How many more toolbar animations are there?

  • There were 2 animations in the previous version of Firefox (downloading and bookmarking). In the new Firefox we have 7 animations (stop-reload, Pocket expansion, bookmarking burst, Pocket library drop, bookmarking library drop, downloading, pin to overflow). That’s an increase of 250%.

Who Says Fast Can’t Also Be Good?

According to real-world performance testing by our army of Mozillians, here’s one more really, really interesting number: the new Firefox is running about 2x faster than our previous build.  Not final. Not fully vetted. But definitely faster.

We hope you’ll feel the excitement and enjoy the new Firefox, too. So until next release, let’s keep these numbers growing and all keep browsing for good!


*Math for all you math whizzes! In Firefox 56 there are 6.204484e+23 (24 factorial) possible configurations of toolbar items (23 factorial if you exclude the non-removable back-forward-location-bar item). In Firefox 57 there are 2.6525286e+32 (30 factorial) possible configurations of toolbar items (28 factorial if you exclude the non-removable back-forward and location bar, including the number of Spacers set at 2 since that’s the default though their usage is not limited)) That means that in Firefox 57 there are 265,252,859,191,742,656,903,069,040,640,000 more ways to customize Firefox (30! – 24!).