Privacy Policy
What tools4free.dev collects, what Google collects when you see ads, and how to control it.
Last updated: 18 October 2026
Who we are
tools4free.dev is run by CJD Technologies LLC. This policy covers the website at tools4free.dev and its tools and study pages.
Contact for privacy questions: support@tools4free.dev.
Summary
- The tools run in your browser. The text, numbers, files and passwords you enter are not sent to us and are not stored by us.
- We use Google Analytics to count visits to pages.
- We show advertisements through Google AdSense. Google may use cookies and similar technology to show ads, and may show personalised ads depending on your consent and your region.
- Some tools contact outside services when you ask them to. Each of those tools says so on its page.
- Your settings and study progress are kept in your browser's local storage, on your device only.
Information we collect
Usage analytics (Google Analytics 4)
We use Google Analytics 4 to measure how the site is used: which pages are viewed, roughly how long visitors stay, and the country or region of a visit. Google Analytics sets cookies to tell visits apart. The data is processed by Google under its own terms. You can opt out with the Google Analytics opt-out browser add-on.
Advertising (Google AdSense)
The site shows ads from Google AdSense. Google and its partners may use cookies, advertising identifiers and similar technology to show ads, measure how they perform, and limit how often you see the same ad. Depending on your region and your choice, the ads may be personalised, meaning they are based on your past visits to this and other sites that use Google's services, or non-personalised, meaning they are not based on those visits.
Google explains how it uses information from sites and apps that use its services at policies.google.com/technologies/partner-sites. You can manage ad personalisation at adssettings.google.com, and find out more about advertising cookies at business.safety.google/adscookies.
Where the law requires it (including for visitors in the European Economic Area, the United Kingdom and Switzerland), we ask for your consent before ads that use cookies or personalisation are shown. You can change your choice at any time using the consent settings offered on the site. To change your choice, email support@tools4free.dev.
Tools that contact outside services
Most tools never contact anyone. The following tools make requests, and each shows a notice on its page:
- What Is My IP asks the ipify service (api.ipify.org and api6.ipify.org) for the public IPv4 and IPv6 address your connection uses.
- DNS Lookup sends the name you enter to Cloudflare's DNS-over-HTTPS resolver (cloudflare-dns.com). Cloudflare sees the name and your IP address.
- Latency Test requests only an image on this site, to time how long requests take. It contacts no other service.
These services have their own privacy policies, which apply to those requests.
Information you enter into tools
Text, numbers, dates, files, passwords and other input you type or choose are used in your browser to produce the result. They are not sent to us. The password tools do not store or send what you type. The hash tool and the hex dump and file inspector read a file you choose in your browser, and the file is not uploaded.
Local storage in your browser
The site keeps a small amount of data in your browser's local storage so that it works as you left it:
- your light or dark theme choice;
- study progress, such as the topics you have ticked off and your flashcard review boxes;
- your remembered choices on some pages.
This data stays on your device. You can clear it at any time in your browser settings, which resets your progress.
Cookies
Google Analytics and Google AdSense set cookies. Cookie names and lifetimes are set by Google and can change. The site's own code does not set cookies. You can control cookies in your browser settings and through the Google links above.
Hosting
The site is hosted on Cloudflare. Cloudflare processes requests to deliver the pages and may keep technical logs, such as IP addresses and request times, under its own privacy policy.
Children
The site is not aimed at children under 13, and we do not knowingly collect information from them.
Your rights
Depending on where you live, you may have the right to access, correct or delete personal data we hold about you, to object to or restrict some processing, and to withdraw consent. Because we do not hold account or form data, most requests are about Google's data, which you can manage through the Google links above. For anything else, contact us at the address above.
If you are in the United Kingdom you can complain to the Information Commissioner's Office at ico.org.uk. If you are in the European Economic Area, you can complain to your local data protection authority.
Your privacy choices (US)
US state privacy laws, such as the California Consumer Privacy Act, give residents the right to know what personal information a business collects, to ask for it to be deleted or corrected, and to opt out of the sale or sharing of personal information. We do not sell personal information. Advertising on this site is served by Google, and under some state laws the information Google uses to personalise ads may be treated as sharing. You can opt out of that in any of these ways:
- Turn off ad personalisation at adssettings.google.com.
- Decline personalised ads when the consent message is shown, or change your choice later through the consent settings on this site.
- Opt out of Google Analytics with the Google Analytics opt-out add-on.
To make a request about your personal information, contact us at the address above. We will not discriminate against you for using your rights.
Changes to this policy
We may update this policy. The date at the top shows when it last changed.