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GNAT Pro vs Mozilla Firefox

GNAT Pro logo

GNAT Pro

Developer Tools

Software development environments and toolchains for Ada, C/C++ and Rust

From
On request
Free plan
No
Full reviewWebsite
Mozilla Firefox logo

Mozilla Firefox

Technology

An independent web browser with its own rendering engine, funded almost entirely by search placement deals.

From
Free
Free plan
Yes
Full reviewWebsite

The short version

  • Only Mozilla Firefox has a free tier, so it costs nothing to try first.
  • Each has a real cost: GNAT Pro no pricing published on website; requires contacting AdaCore directly for quotes; Mozilla Firefox roughly 85 per cent of Mozilla's revenue comes from search default placement deals, overwhelmingly with Google, so the organisation that competes with Chrome depends on Chrome's owner for its funding and any renegotiation lands on Firefox's engineering budget within a quarter.
  • Prices and features above were last checked on 30 August 2026.

Where they differ

Only the attributes on which GNAT Pro and Mozilla Firefox actually diverge.

Attributes where GNAT Pro and Mozilla Firefox differ
AttributeGNAT ProMozilla Firefox
Starting priceOn requestFree
Pricing modelquoteUnknown
Free tierNoYes
PlatformsWebWindows, macOS, Linux, iOS, Android
CategoryDeveloper ToolsTechnology
FoundedUnknown2004

Identical on both: user rating (Not yet rated).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in GNAT Pro

Nothing recorded that Mozilla Firefox does not also cover.

Only in Mozilla Firefox

  • Gecko engine
  • Full webRequest blocking
  • Total Cookie Protection
  • Container tabs
  • Extended Support Release
  • policies.json and ADMX
  • Built-in developer tools
  • Firefox Sync

What people use each for

The jobs each tool is most often brought in to do.

GNAT Pro

  • Building certified avionics software meeting DO-178B/C standardsnot Mozilla Firefox
  • Developing automotive embedded systems with ISO-26262 compliancenot Mozilla Firefox
  • Integrating Ada, C/C++, and Rust components in single codebasenot Mozilla Firefox
  • Managing software supply chain vulnerabilities and SBOMsnot Mozilla Firefox
  • Supporting long-lived software systems spanning decadesnot Mozilla Firefox

Mozilla Firefox

  • Web development where you need to test against a non-Chromium engine before shipping, because Chromium-only testing hides real bugsnot GNAT Pro
  • Users who require a full-strength content blocker, which Chrome's Manifest V3 no longer permitsnot GNAT Pro
  • Managed fleets that need a browser on a slow release cadence with Group Policy control, using the ESR channelnot GNAT Pro
  • Handling several accounts on the same service at once through container tabs, without separate profiles or private windowsnot GNAT Pro

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

GNAT Pro

  • No pricing published on website; requires contacting AdaCore directly for quotes
  • Vendor indicates per-user, per-year subscription model but does not disclose specific costs

Mozilla Firefox

  • Roughly 85 per cent of Mozilla's revenue comes from search default placement deals, overwhelmingly with Google, so the organisation that competes with Chrome depends on Chrome's owner for its funding and any renegotiation lands on Firefox's engineering budget within a quarter.
  • Desktop market share sits at a few per cent, so commercial sites are tested against Chrome and Safari and a Firefox-only rendering or WebRTC bug is triaged as low priority by the site owner, leaving you with the workaround.
  • On iOS and iPadOS the browser is a WebKit shell required by Apple's rules, so it delivers the interface and Sync but none of the engine, extension or tracking-protection behaviour that make Firefox worth choosing on desktop.
  • Mozilla declines to implement several hardware-facing APIs on principle, including WebUSB, WebSerial, Web Bluetooth and WebHID, so a web application that talks to a device simply does not run and no configuration flag changes that.
  • Enterprise management is limited to policies.json and ADMX templates; there is no first-party equivalent of Chrome Browser Cloud Management, so fleet-wide reporting on versions and extensions requires third-party tooling you have to buy or build.
  • Mozilla repeatedly ships decisions its own user base objects to, such as enabling Privacy Preserving Attribution by default and the 2025 Terms of Use rewrite, and reversals arrive after the news cycle, so deploying it on a privacy argument means owning the communications work each time.

Pricing, plan by plan

GNAT Pro

On request

No published plan breakdown. See the GNAT Pro review.

Mozilla Firefox

Free

No published plan breakdown. See the Mozilla Firefox review.

Which should you pick?

Choose GNAT Pro if

Nothing in the data separates GNAT Pro from Mozilla Firefox on the points above - pick on price and on how each one feels to use.

GNAT Pro review

Choose Mozilla Firefox if

  • You need gecko engine.
  • You want to start without paying.
  • You work on Windows, macOS, Linux, iOS, Android.
  • You also want full webrequest blocking.
Mozilla Firefox review

Questions people ask

Is GNAT Pro or Mozilla Firefox better?
Neither clearly leads. GNAT Pro starts at On request and Mozilla Firefox at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, GNAT Pro or Mozilla Firefox?
Mozilla Firefox has a free tier; the other does not. Paid plans start at On request for GNAT Pro and Free for Mozilla Firefox.
Does GNAT Pro or Mozilla Firefox run on more platforms?
GNAT Pro runs on Web. Mozilla Firefox runs on Windows, macOS, Linux, iOS, Android.
Can I use Mozilla Firefox for free?
Yes. Mozilla Firefox has a free tier, so you can try it without paying. GNAT Pro starts at On request.
What is GNAT Pro best used for?
GNAT Pro is most often used for building certified avionics software meeting do-178b/c standards, developing automotive embedded systems with iso-26262 compliance, integrating ada, c/c++, and rust components in single codebase, managing software supply chain vulnerabilities and sboms. Of those, building certified avionics software meeting do-178b/c standards and developing automotive embedded systems with iso-26262 compliance are not what Mozilla Firefox is typically brought in for.
What can GNAT Pro do that Mozilla Firefox cannot?
Mozilla Firefox covers Gecko engine, Full webRequest blocking, Total Cookie Protection, Container tabs.

Answered from the vendors’ own pages

GNAT Pro: How much does GNAT Pro cost?

GNAT Pro pricing is not published on the website. Customers must request a pricing quote by contacting AdaCore directly or speaking with a GNAT Pro expert.

Source
Mozilla Firefox: Does uBlock Origin still work on Firefox?

Yes. Firefox has kept the blocking webRequest API that Chrome removed with Manifest V3, so uBlock Origin runs with its full rule set rather than the cut-down Lite version Chrome requires.

GNAT Pro: What is GNAT Pro licensing model?

GNAT Pro is sold on a per-user, per-year basis with no license locks. Customers can request pricing for their specific needs.

Source
Mozilla Firefox: Is Firefox on iPhone the same browser?

No. Apple's platform rules require it to use WebKit, so on iOS and iPadOS you get Firefox's interface, Sync and bookmarks on top of Safari's engine. The privacy and extension behaviour are not the same.

Mozilla Firefox: How is Mozilla funded, and does that matter?

Mainly by payments for making a search engine the default, with Google as the dominant payer. It matters because it is a single-source dependency on a direct competitor, and it has been the subject of antitrust litigation whose outcome Mozilla does not control.

Mozilla Firefox: Can I manage it across a company fleet?

Yes, through policies.json or Windows Group Policy with the ADMX templates, and the ESR channel gives you a roughly yearly major version instead of four-weekly. There is no first-party cloud management console, so reporting needs other tooling.

Mozilla Firefox: Will every site work in it?

Most will. The exceptions cluster around sites tested only in Chrome, legacy enterprise applications, and anything using WebUSB, WebSerial, Web Bluetooth or WebHID, which Firefox does not implement at all.

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