Privacy Policy
Last updated: 18 August 2026
This policy explains what happens to data when you use FormatStack (formatstack.tech). It covers two separate things that are easy to confuse: what you type into the tools, and what your browser reveals by visiting the site at all. They are handled very differently, so they are described separately below.
The short version: anything you paste into a tool stays in your browser and is never sent to us or anyone else. The site itself does use Google AdSense and Google Analytics, and those services set cookies and collect data about your visit in the ordinary way.
1. Your tool input is never transmitted
Every tool on this site — the JSON formatter, regex tester, UUID generator, Base64 encoder and decoder, and cron parser — is implemented entirely in JavaScript that runs inside your own browser. There is no backend that processes your input.
This means that the JSON you paste, the regular expressions and test strings you type, the text you encode or decode, and the cron expressions you parse are:
- never sent over the network to this site or to any third party;
- never written to a server, database, or log file;
- never stored after you close or reload the tab.
You can verify this yourself: open your browser's developer tools, switch to the Network tab, and use any tool on the site. You will see no request carrying your input, because none is made.
One consequence worth noting: because nothing is stored, there is nothing to recover. If you close the tab, your input is gone.
2. Information collected automatically
Visiting any website reveals some information by necessity. When you load a page here, standard technical information is processed — including your IP address, browser type and version, operating system, referring page, and the pages you view. This is used to keep the site running, understand which tools people find useful, and serve advertising.
No account is required to use FormatStack, and there is no registration, login, newsletter, or contact form. Personal details such as your name or email address are only ever received if you choose to email the address on the contact page, in which case they are used solely to reply to you.
3. Cookies
Cookies are small text files that a site or its partners store in your browser. FormatStack itself does not set cookies for logins or preferences, because it has neither. However, the third-party services described below do set cookies on this site.
You can control or delete cookies in your browser settings at any time. Every major browser lets you block third-party cookies, delete existing ones, or refuse them entirely. Blocking them will not stop any tool on this site from working, since the tools do not depend on cookies.
4. Google AdSense advertising
This site displays advertising served by Google AdSense in order to remain free to use. The following disclosures apply:
- Third-party vendors, including Google, use cookies to serve ads based on your prior visits to this website and other websites.
- Google's use of advertising cookies enables it and its partners to serve ads to you based on your visit to this site and/or other sites on the internet.
- Google uses the DoubleClick DART cookie and similar technologies for this purpose.
- Third-party vendors and ad networks other than Google may also serve ads on this site and may likewise use cookies, web beacons, or similar technologies to measure ad effectiveness and personalise the ads you see.
FormatStack does not control these cookies, does not have access to the data they collect, and cannot read or modify them.
Opting out of personalised advertising
- You may opt out of personalised advertising by visiting Google Ads Settings.
- You may opt out of some third-party vendors' use of cookies for personalised advertising at aboutads.info/choices or the Network Advertising Initiative opt-out page.
- Opting out means you will still see ads, but they will not be personalised based on your browsing history.
For a full account of how Google handles information from sites that use its services, see How Google uses information from sites or apps that use our services and the Google Privacy Policy.
5. Google Analytics
This site uses Google Analytics to understand how visitors use it — which tools get used, which pages people arrive on, and roughly where in the world traffic comes from. Google Analytics sets cookies and collects usage data including your IP address, device and browser information, pages visited, and time spent on the site.
This information is used in aggregate to improve the site. It is not used to identify individual visitors, and it is never combined with anything you type into a tool — as described in section 1, that input never reaches any server in the first place.
If you would rather not be included in Analytics measurement at all, Google publishes a browser add-on that opts you out of Google Analytics across all sites. Google's handling of this data is governed by the Google Privacy Policy.
6. Hosting
The site is served as static files by a third-party hosting provider. Like any web host, it processes the technical request information described in section 2 (such as IP addresses) in order to deliver pages to you and to protect against abuse.
7. Data retention
Because tool input is never collected, there is nothing to retain. Analytics and advertising data are retained by Google according to its own retention policies, which are described in the Google documents linked above. Email you send to the contact address is kept only as long as needed to deal with your message.
8. Your rights
Depending on where you live, you may have rights over personal data relating to you — including the right to access it, correct it, delete it, or object to its processing. Since the data collected on this site is held by Google rather than by FormatStack, requests about advertising and analytics data are best directed to Google through the links above, where you can also view and delete the data associated with your Google account. For anything else, contact the address on the contact page.
9. Children's privacy
FormatStack is a set of tools for software developers and is not directed at children under 13. No information is knowingly collected from children.
10. External links
Some pages link to external sites, such as Google's policy documentation. Those sites have their own privacy policies, and FormatStack is not responsible for their content or practices.
11. Changes to this policy
This policy may be updated as the site changes — for example if an advertising or analytics provider is added or removed. Any revision will be posted on this page with an updated date at the top. Material changes will be reflected here rather than announced individually, so it is worth re-reading this page if you use the site regularly.
12. Contact
Questions about this policy can be sent to singh@harmanjudge.com, or via the contact page.