Kinto is a lightweight JSON storage service with synchronisation and sharing abilities. It is meant to be easy to use and easy to self-host.

Kinto is used at Mozilla and released under the Apache v2 licence.

Use cases

  • A generic Web database for frontend applications.
  • Build collaborative applications with fine-grained permissions.
  • Store encrypted data at a location you control.
  • Synchronise application data between different devices.

Key features

https://thenounproject.com/search/?q=syncing&i=31170 Synchronisation https://thenounproject.com/search/?q=offline&i=90580 Offline-first JS client
https://thenounproject.com/search/?q=permissions&i=23303 Fined grained permissions https://thenounproject.com/search/?q=community&i=189189 Plug multiple clients
https://thenounproject.com/search/?q=free&i=669 Open Source and Self-hostable https://thenounproject.com/search/?q=community&i=189189 Designed in the open


Coming soon

  • Schema validation
  • Push notifications


Bi-directionnal synchronisation of records is a very hard topic.

Kinto takes some shortcuts by only providing the basics for concurrency control and polling for changes, and not trying to resolve conflicts automatically.

Basically, each object has a revision number which is guaranteed to be incremented after each modification. Kinto does not keep old revisions of objects.

Clients can retrieve the list of changes that occured on a collection of records since a specified revision. Kinto can also use it to avoid accidental updates of objects.



Kinto synchronisation was designed and built by the Mozilla Firefox Sync team.

Comparison with other solutions

Before we started building our own data storage service, we took a look at what was already out there. Our initial intent was to use and possibly extend an existing community project rather than reinventing the wheel.

However, since none of the existing solutions we tried was a perfect fit for the problems we needed to solve, notably regarding fine-grained permissions, we started our own stack using the experience we gained from building Firefox Sync.

What follows is a comparison table showing how Kinto stacks up compared to some other projects in this space.

Project Kinto Parse Firebase CouchDB Remote-Storage Hoodie
Fine-grained permissions     [1]
Easy query mechanism [2] [3]
Conflict resolution [4]
Revision history        
File storage    
Batch/bulk operations    
Changes stream [5]  
Pluggable authentication     [6]
Pluggable storage / cache        
Decentralised discovery [7]        
Open source    
Language Python     Erlang Node.js [8] Node.js
[1]Currently, user plugin in Hoodie auto-approves users, but they are working on it.
[2]CouchDB uses Map/Reduce as a query mechanism, which isn’t easy to understand for newcomers.
[3]Remote Storage allows “ls” on a folder, but items are not sorted or paginated.
[4]Kinto uses the same mechanisms as Remote storage for conflict handling.
[5]Notifications support is currently in the work.
[6]Remote Storage supports OAuth2.0 implicit grant flow.
[7]Support for decentralised discovery is planned but not implemented yet.
[8]Remote Storage doesn’t define any default implementation (as it is a procol) but makes it easy to start with JavaScript and Node.js.

You can also read a longer explanation of our choices and motivations behind the creation of Kinto on our blog.


How does Kinto compares to CouchDB / Remote Storage?

To see how Kinto compares to CouchDB & Remote Storage, read the comparison table.

Can I encrypt my data?

Kinto server stores any data you pass to it, whether it’s encrypted or not. We believe encryption should always be done on the client-side, and we make it easy to use encryption in our Kinto.js client using transformers.

Is there a package for my Operating System?

No, but it’s a great idea. Maintaining packages for several platforms is time-consuming and we’re a small team. At this time we’re just making sure it’s easy to run our server using our Makefile or our Dockerfile.

Kinto is easy to install with pip and we’ve got an image set up on the Docker hub, too.

But if you’d like to help us out by maintaining packages for your favourite OS, we’d be delighted to collaborate with you!

Why did you chose to use Python rather than X?

We love Python because it’s a concise & expressive language with powerful data structures & easy to learn, so it was an obvious choice for the development team.

In addition, the Operations team at Mozilla is comfortable with deploying and managing Python applications in production.

However, Python is just an implementation detail per se. Kinto is defined by an HTTP protocol that could be implemented in any language.

Is it Web Scale?

YES™. Have a look at the /dev/null backend. ;-)

Can I store files inside Kinto?

Not yet, but we’ve designed a file storage feature and we’re working on its implementaton. It should land in a release sometimes in 2016.

In the meantime, we’re always looking for early feeback if you want to try our cutting edge version.

What is Cliquet? What is the difference between Cliquet and Kinto ?

Cliquet is a toolkit for designing micro-services. Kinto is a server built using that toolkit.

Read more (in french) about the differences.

I am seeing an Exception error, what’s wrong?

Have a look at the Troubleshooting section to see what to do.