This free online tool shows x509 certificate information. You can use it to dump information about Android APK or bundle signatures.

Note: This tool is completely client-based and all processing is done on your device. That means your files are not transferred to the server.

If you you're an Android enthusiast that likes to learn more about Android internals, I highly recommend to check out the Bugjaeger app. It allows you to connect 2 Android devices through USB OTG and perform many of the tasks that are normally only accessible from a developer machine via ADB directly from Android phone/tablet.

What Certificate Information Can You Find

Currently you can dump various information from certificate stored in DER binary format/PKCS7 standard (used by Android APK files).

This tool should dump the following information

  • Issuer and Subject (e.g. CN, ...this allows you to find the person who signed the APK)
  • Validity period of the certificate (Not before, Not after dates)
  • Encryption algorithm
  • Signature algorithm
  • RSA Publick-Key length
  • Other stuff

You Want Other Information or Something Is Not Working

In case something wasn't working, or you would like to use other certificate formats (e.g. PEM), or you would additionally like to verify if APK signature is correct, write directly to my email roman@sisik.eu.

I'll try to fix bugs and add requested features if possible.

Other Useful Tools

If you want to get detailed information about Android's APK files, check out my APK Analyzer tool.

Additionally, if you you're an Android enthusiast that likes to learn more about Android internals, I highly recommend to check out the Bugjager app. It allows you to connect 2 Android devices through USB OTG and perform many of the tasks that are normally only accessible from a developer machine via ADB directly from Android phone/tablet.

Sixo Apps

If you're curios about the technical aspects of Android or you like image & video processing apps, you might find something interesting amongst the apps that I've published on Google Play