Pontoon

Mozilla open source localisation platform that you host yourself

As of 30 August 2026, Pontoon is free to use. The translation system Mozilla built to localise Firefox with volunteer communities, released as open source with no hosted commercial edition. Softwr lists it under Translation. Pontoon is made by Mozilla, available on Web, Self-hosted.

Visit siteVisit Pontoon

Overview

What Pontoon does

Pontoon is a Django application for managing software localisation. It syncs strings from a version control repository, presents them to translators in a review interface with translation memory suggestions, machine translation proposals and terminology, runs a suggest and approve workflow with per locale reviewer roles, and commits approved translations back to the repository. It is strongest with gettext PO and Mozilla Fluent, the format Mozilla created for translations that need grammatical variation. The licence is what changes the calculus. Because it is open source and self-hosted, cost scales with your server rather than your contributor count, which is the only reason a project with hundreds of volunteer translators across sixty locales can run a real workflow without a five figure bill. It also means there is no hosted service to sign up for: you provide Django, PostgreSQL, a task queue and the operational attention to keep them running, and you supply your own machine translation API keys. Buyers are open source projects and organisations with community translation programmes that already run their own infrastructure. The trade-off is support: the roadmap follows Mozilla priorities, the deployment documentation assumes engineering familiarity, and nobody owes you a fix.

What people use it for

Open source projects with volunteer translator communities across many locales
Organisations that must keep translation data on their own infrastructure
Projects using Mozilla Fluent where commercial tools have partial or no support
Replacing a per seat translation platform where contributor count, not word volume, drives the bill

Where it falls short

Concrete and checkable, so you can decide whether any of them matter to you. This is the half of a review a vendor will not write about Pontoon.

There is no hosted commercial edition, so adopting it means running Django, PostgreSQL and a task queue yourself and keeping them patched.
No vendor support and no service level agreement exist, so an outage during a release freeze is your engineering problem alone.
The roadmap serves Mozilla localisation needs first, and features outside that scope are unlikely to be built for you.
Format coverage is narrow next to commercial systems: it is strong on PO and Fluent, weak on document formats such as InDesign or complex XML.
Because you host it, security and compliance evidence such as an external audit report does not exist, so any assurance your customers need has to be produced by your own team.

Cross-shopped

What people choose instead of Pontoon

Each pairing was judged by two reviewers asking whether a buyer would genuinely weigh the two against each other. The ones that failed were deleted rather than published.

Pontoonvs
Crowdin
Crowdin: Hosted equivalent with vendor support and far wider file format coverage
Pontoonvs
Transifex
Transifex: Choose when community translation still needs commercial support and reporting
Pontoonvs
Weglot
Weglot: Different approach entirely: translates a live site by proxy with no repository workflow

Pricing

What Pontoon costs

Taken from the vendor's own pricing page. Prices move, so check before you buy.

Open source, self-hosted

Free

No licence fee and no per contributor charge
You provide hosting, database and maintenance
Machine translation billed by whichever engine you connect
Support is community only through GitHub and Matrix

Capabilities

Features

Repository sync
Reads source strings from and commits translations back to Git
Suggest and approve workflow
Volunteers propose translations and per locale reviewers accept or reject them
Fluent support
Handles Mozilla Fluent files including plural and gender variants
Translation memory
Suggests previous approved translations from the same project
Machine translation suggestions
Calls external engines using keys you supply
Contributor statistics
Tracks per locale completion and reviewer activity for community management

Answered, with sources

Questions people ask

Each answer names the page it came from, so you can check it rather than take our word for it.

Is there a paid hosted version?

No. Mozilla runs an instance for its own projects. Anyone else deploys their own.

What does it actually cost?

Server hosting, engineering time to operate it, and whatever machine translation engine you connect. There is no licence fee.

Is it suitable for a commercial product?

Only if you have infrastructure staff and mostly software string formats. Document translation and vendor support are missing.

Keep looking

Where to go from Pontoon

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Softwr does not host reviews and shows no star rating for Pontoon, because a rating we did not collect is not ours to publish. What is here is the pricing and platform detail from the vendor’s own pages, limitations we could state concretely, and alternatives a reviewer confirmed people weigh against it. Tell us if any of it is wrong.

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