JsonFlex
Privacy & cookies
Last updated 1 October 2026
The short version
- Your JSON never leaves your browser. Whatever you paste, type or open is parsed, formatted, sorted and edited on your own device. None of it is sent to us or to anyone else.
- There are no accounts. No sign-up, no login, no email address needed to use JsonFlex.
- There are no cookies. JsonFlex sets none at all.
- There is no analytics and no tracking of any kind. We do not count visits, and no third-party script runs on this site.
What happens to the document you work on
JsonFlex runs in your browser. When you open the site your browser downloads the program itself - the same fixed set of HTML, CSS and JavaScript files everyone gets - and then runs it locally. From that point on, the parser, the formatter, the tree view and everything you paste, type or open live in the browser tab in front of you.
We do not receive the document you work on, and we could not, because nothing in
the app sends it anywhere. Once those files have loaded, the app's code makes no
network request of any kind - no upload, no API call, no background connection -
and the host exposes no API of its own: its only job is to hand over the
application files. Opening a
local .json file (up to 20 MB) reads it straight
into the editor through the browser's own file picker; the file is never uploaded.
Using Copy reads the document from the editor and writes it to
your system clipboard, again without it going anywhere else.
In practice this means you can disconnect from the network once the app has loaded and carry on working, and it means that pasting or opening confidential or personal data in JsonFlex does not disclose it to us. What you do with that data remains yours to govern; if it is personal data, you stay its controller.
How to check this yourself
You do not have to take our word for any of the above. Open your browser's developer tools, switch to the Network tab, and use JsonFlex normally: paste or open a document, format it, sort it, switch to the tree view, edit a value. After the initial load of the application files you will see no request carrying your content, because none is made. Or simply go offline after the app has loaded and watch it keep working.
What is stored on your device
JsonFlex remembers your document and your view settings so that closing the tab does not throw them away, and it remembers your theme choice separately. Both live entirely on your own computer, in two different browser stores. Nothing written to either is transmitted to us or to anyone else, and nothing in them is readable by another website.
| Name | What it holds | Why |
|---|---|---|
jf-session |
The document text, which view is showing, the format style and the sort order, in your browser's IndexedDB. A document too large to store (over 20 million characters) is left out, and the status bar says so. | So a reload or an accidentally closed tab does not lose your document. |
jf-theme |
Light or dark, if you have chosen one, in your browser's local storage. | So the app opens in the theme you picked. |
You can remove all of it at any time by clearing site data for this site in your browser's settings - in most browsers, through the padlock or information icon in the address bar. Doing so loses the remembered document and theme and nothing else. If you would rather nothing were kept at all, a private or incognito window discards it when you close the window.
Cookies
JsonFlex sets no cookies. Not for sessions, not for settings, not for analytics, not for advertising - there are none.
UK law on cookies - the Privacy and Electronic Communications Regulations 2003 - covers not only cookies but any storage of, or access to, information on your device, which includes the IndexedDB record and the local storage entry described above. It requires consent for that, except where the storage is strictly necessary to provide a service you have explicitly requested. Both items above are of that kind: they exist only to give you back the document and the theme you chose. They are not used to recognise you, to build a profile, or for any purpose other than the one stated beside each of them. That is why JsonFlex has no cookie banner: there is nothing to ask you to agree to.
Server logs
Like every website, the server that hands out the JsonFlex application files keeps standard access logs. These record the IP address making the request, the time, the file requested, the response status and the browser's user-agent string. They are generated by the web server itself, not by the app, and they never contain anything you typed, pasted or opened - only the fixed file names that make up the program.
We use them to keep the site available and secure and to investigate faults and abuse. The lawful basis is legitimate interests (UK GDPR Article 6(1)(f)). They are retained for no longer than 30 days and are not used to build any profile.
Who handles your information
JsonFlex has no third-party services embedded in it - no advertising, no trackers, no analytics, no social media widgets, no external fonts, and no content delivery networks. The only organisation involved besides us is the company that hosts the server, acting on our instructions under a contract, and the only information it handles is what the server logs section describes.
The server is located in the European Economic Area, which UK adequacy regulations cover, so no transfer safeguards beyond that are needed. We do not transfer anything outside the UK or the EEA.
Your rights
Under the UK GDPR you have the right to be informed, and rights of access, rectification, erasure, restriction of processing, data portability and objection, as well as the right not to be subject to automated decision-making. JsonFlex makes no automated decisions about anyone and does no profiling.
Because we hold nothing that identifies you, there is in practice very little for these rights to reach: we cannot look you up, because there is nothing to look up by. The exception is a server log entry, which we can find only if you can tell us the IP address and the approximate time. You are welcome to ask, and to object to the processing described above, at the address below.
If you are unhappy with how we have handled your information, you can complain to the Information Commissioner's Office, the UK's data protection regulator, at ico.org.uk/make-a-complaint or on 0303 123 1113. We would rather you raised it with us first so we have a chance to put it right.
Children
JsonFlex is a tool for working with JSON and is not directed at children. It asks for no personal information from anyone, of any age.
Security
The site is served only over HTTPS, with HTTP Strict Transport Security, so the application files cannot be tampered with in transit. Since your document stays in your browser, the strongest protection it has is the one your own device provides.
Changes to this notice
If JsonFlex changes in a way that affects any of this - and in particular if it ever gains a feature that sends your data anywhere, or an analytics script - we will update this page and change the date at the top before that feature ships.
Contact
For anything about this notice, or to exercise any of the rights above, write to jsonflex+privacy@vsrc.uk.