Derpibooru Privacy Policy

The privacy policy was last updated

We may update this document in the future, and will provide a site notice when we do.

The short version

We collect only the bare minimum amount of information that is necessary to protect the service against abuse. We do not sell your information to third parties, and we only use it as this document describes. We aim to be compliant with the EU GDPR.

What information Derpibooru collects and why

Information from webserver logs

We collect the following information (in webserver logs) from every visitor:

  • The visitor Internet Protocol (IP) address
  • The date and time of the request
  • The page that was requested
  • The browser user agent string

These items are collected to ensure the security of the service, and are deleted after 14 days to balance our "legitimate interest" (as mentioned in the GDPR) of security with user privacy.


Information in cookies

Our cookies for any users of the service may contain this information:

  • The unique session token for the website
  • User preference for loading high-resolution images
  • User preference for loading video previews of animated images
  • User preference for website layout customization
  • User preference for filtering settings
  • One or more "flash" messages (temporary notifications of an action's success or failure, to be displayed at the top of the next page load and then deleted)
  • A browser fingerprint (see below)

Additionally, cookies of users that are logged into the service will contain this information:

  • An encrypted authentication secret unique to the user to persist their login

We might add to this list in the future as needed.

These are required for authentication, user security, or customization, which are all "legitimate interests" as above, and thus we cannot ask for consent to use cookies.


Information in user-submitted content

User-submitted content is considered by Derpibooru to collectively refer to any content that you may submit to the site, which includes, but is not limited to, comments, images, messsages, posts, reports, source changes, tag changes, and votes.

User-submitted content by users (authenticated or not) may contain any or all the following information:

  • The IP address at the time of submission
  • The browser fingerprint at the time of submission (see below)
  • The browser user agent string
  • The page on Derpibooru that initiated the submission

These items are only used for the "legitimate interests" of identifying and controlling abuse of the service and are not shared with any external party.


Browser fingerprints

Browser fingerprints are a tool used to identify users of the service in such a way that administrators will have no knowledge of the individual components of a fingerprint. They are irretrievably hashed (by a browser script) from the following attributes:

  • Browser version
  • Screen width, height, and color depth
  • Timezone offset
  • Browser support for storage API
  • Browser plugins

Information from users with accounts

If you create an account we require some basic information at the time of account creation. You will be asked to provide:

  • a username, shown on your profile and non-anonymous user-submitted content
  • a password, stored only as a cryptographic hash
  • an email address, used only for sending password resets or account unlocking instructions

We also store your IP address whenever you log in for security reasons.

Information that Derpibooru does not collect

We do not intentionally collect personal information, but users may include it in user-submitted content. We will remove personal information if we deem it too sensitive. Inform us if you believe shared information is too sensitive.

This is especially important because information shared in public user-submitted content may be indexed by search engines or used by third parties without your consent.

Information that may potentially be shared with third parties

We do not in any way share individual account information with third parties except in response to court orders. We make public certain statistics about how users use Derpibooru (for example, about uploads), without personally-identifying information.

Most of Derpibooru is public-facing, and third parties may access and use it.

Our advertising network, Project Wonderful, may see your IP address, but nothing else.

How we secure your information

Derpibooru takes all measures reasonably necessary to protect account information from unauthorized access, alteration, or destruction.

While in transit, your data are always protected by the latest version of Transport Layer Security (TLS) our software supports. Between our data processor Cloudflare and our service, we use HTTPS with an elliptic P-384 key. To protect user data on our servers, we strictly limit their access, and require the use of elliptic Ed25519 or 4096-bit RSA keys for server login.

HTTPS is required for all connections to our service. Our cookies use a "secure" setting and may only be transmitted privately to Derpibooru. We use a restrictive content security policy to protect against page hijacking and information leakage to third parties, an image proxy server to avoid leaking user IP address information from embedded images on the site, a cross-origin resource sharing (CORS) policy to restrict third-party usage, a strict referrer policy to prevent leaking data for external links, and an frame policy to prevent clickjacking.

Passwords are hashed using bcrypt at 2^10 iterations with a 128-bit per-user salt.

No method of transmission, or method of electronic storage, is 100% secure. Therefore, we cannot guarantee its absolute security; we only make a best effort.

Resolving complaints

If you have concerns about the way Derpibooru is handling your personal information, please let us know immediately. You may contact us by emailing us directly at ops@derpibooru.org.