Updates to MDC REST API and Python Library

Tl;dr: Update to newest version of the MDC Python library (0.2.0 or newer) to continue downloading datasets

FAQ: How long does it take to publish my dataset on MDC?

We review every request to become a data provider on Mozilla Data Collective. Reviewing Uploader Requests If you have not already been in contact with our team about uploading data to Mozilla Data Collective, a member of our team will reach out to you via email to discuss your dataset

Pashto becomes third-highest language by volume of data in Common Voice v24

Key highlights from the Common Voice v24 Scripted Speech and v2 Spontaneous Speech release.

FAQ: How can I contribute to Mozilla Data Collective?

We are a collective of linguists, technologists, activists, researchers and creatives. Whether you’re interested in stewarding data, conducting research, developing new AI and ML technologies, or just want to be part of our community working to make AI all it promises to be - not all it threatens to

FAQ: Do I need to be part of an organization to upload a dataset to Mozilla Data Collective?

No, you do not need to be a part of an organization to upload a dataset to Mozilla Data Collective. We recognize that there are many use cases where an individual might want to share datasets that they have created, either on their own or on behalf of a group.

Improving the Spontaneous Speech English dataset: lifting the lid on speech data quality uplift techniques

Firstly, we’d like to thank you for your patience. After introducing Spontaneous Speech early in 2025, we released most locale datasets when the Mozilla Data Collective platform launched in alpha in September of this year. However, upon inspection, the English Spontaneous Speech dataset required some remedial work prior to

Uploading your dataset to the Mozilla Data Collective Platform

Interested in joining the movement and publishing your dataset on Mozilla Data Collective? This guide will walk you through the steps required, from account creation to submission!

FAQ: What does it mean to exclusively host my dataset on Mozilla Data Collective?

When you upload a dataset to Mozilla Data Collective, you have the option to make your dataset exclusive to MDC. The default terms of use for data providers on the platform is that datasets are exclusive to MDC. Choosing to host your dataset exclusively with MDC means that you do

FAQ: What kind of datasets can I publish on Mozilla Data Collective?

Our priority is technology that is more multilingual, multicultural, and multi-modal. We prioritise helping communities unlock content that is not on the web already, and prefer audio, image, and video formats, though we will also accept text documents that advance the above goals. Our expectation is that each dataset is

FAQ: What are the main points of the MDC Terms of Use?

About downloading and using datasets When downloading a dataset, am I getting permission to use it from Mozilla Data Collective or the Data Provider? When you download a dataset from Mozilla Data Collective, you are entering into an agreement with the Data Provider who published the dataset. Data Providers set

What do the languages Nahuatl, Bahasa Indonesia and Bulgarian have in common?

Nahuatl, Bahasa Indonesia and Bulgarian all feature in our very first community curated datasets to be uploaded to the Mozilla Data Collective platform.

FAQ: Why can’t I download old versions of Common Voice datasets?

In order to better serve our community and to keep up with current changes in best practices for data stewardship, we are changing how previous releases of the Common Voice datasets are accessed. They will now be accessible to interested researchers and others via an email-based request process. You will

Common Voice

We're Changing Access to Older Versions of Common Voice datasets

We’re tightening the circulation of old datasets to protect contributors, while keeping a clear, documented path for researchers who need them.

FAQ

FAQ: I've noticed an issue with a data listing - what do I do?

If you discover a minor issue with the accuracy of a data listing on Mozilla Data Collective (a typo, missing attribute in datasheet, etc.) and want to bring it to the attention of the data provider, reach out to the point of contact as specified in the data listing. If

Kick-off of the Shared Task: MCV Spontaneous Speech

Join us for the official kick‑off of the Shared Task: Mozilla Common Voice Spontaneous Speech! This live, online gathering will bring together researchers, engineers, and language‑technology enthusiasts from around the world to launch the challenge focused on building robust, multilingual ASR systems for under‑represented languages. In a

FAQ

FAQ: Why can't I re-host or share Common Voice datasets that I download from MDC?

Mozilla Data Collective wants to provide effective, ethical stewardship support for datasets. This is challenging or impossible when datasets are mirrored or split across a range of forks. Our principles include trying to enable good governance, e.g. the right to be forgotten, as much as possible, which means we

News

Shared Task: Mozilla Common Voice Spontaneous Speech ASR

Quick links * Registration Form * Link to datasets * Codabench page (to submit results during the testing period) * Contact: sharedtask@mozillafoundation.org Overview Automatic speech recognition (ASR) has come a long way – but most systems are still trained on polished, read-aloud speech. So we set out to build a model that can

Common Voice 23.0 Live On Mozilla Data Collective

Common Voice 23.0 is now live – and available for download via Mozilla Data Collective.  Mozilla Data Collective is a sister platform from the team behind Common Voice, designed to let dataset owners and creators offer their data on their own terms. Mozilla Data Collective was built in response to

Mozilla Data Collective Alpha Goes Live

Mozilla Data Collective is now in live alpha, offering the Common Voice 23.0 datasets.

token

Your datasets, under your control: Mozilla Data Collective at PyConAU in Melbourne, Australia

Kathy Reid's presentation to PyConAU in Melbourne, Australia covers tokenomics, harvesting tokens, and how Mozilla Data Collective offers a better way forward.

FAQ

FAQ: What is the MDC Public API?

The Mozilla Data Collective REST API provides a way for developers to access datasets from their own applications, using the programming language of their choice. Users must agree to dataset terms through the web interface before downloading. Each download token can only be used for one complete download session, and

FAQ

FAQ: Can I get the Common Voice or other MDC datasets from other platforms like GitHub or Hugging Face?

We have no plans to host Mozilla community datasets through third parties at this time, as it makes governance and stewardship extremely challenging. For example, when someone chooses to revoke their consent to be included in a dataset, we need a way to remove them from the dataset and update

News

Roadmap

We're excited to share a high-level roadmap for the Mozilla Data Collective platform, leading up to our 1.0 launch in early Q1 2026: September: Mozilla Data Collective Alpha Launch October: New Datasets Available November: Mozilla Data Collective Beta Launch * Dataset and datasheet on-boarding and upload flow * Feature

FAQ

FAQ: What is the long-term sustainability model for Mozilla Data Collective?

We are a mission-driven, community-centred tech organisation being incubated within Mozilla Foundation. Mozilla Data Collective anticipates that we will have both social enterprise and non-profit components eventually, as we think that in today’s volatile, politicised grant funding environment, it’s never been more important to be independent.  Our business