CER Converter

Convert CER files online for free

Select File
Drop or upload your .CER file

How to convert your CER file

Click Select File above, and choose your CER file.
You'll see a preview.
Click the "Convert file to..." button to save your file in the format you want.

Convert CER to another file type

The converter easily converts your CER file to various formats—free and online. No Excel or extra software needed.

CER to PEM
CER to PFX
CER to CRT
CER to P12
CER to JKS
CER to HTML
CER to HTM
CER to CSS
CER to JS
CER to PHP
CER to ASP
CER to ASPX

Convert a file to CER

The converter also works in reverse, allowing you to convert your file into the CER file type—in the best quality.

RSS to CER
CSS to CER
CGI to CER
SITEMAP to CER
PL to CER
WEBMANIFEST to CER
JSON to CER
JS to CER
XML to CER
HTML to CER
ICO to CER
HTM to CER

About CER files

CER files are a type of file used to store digital certificates. They are used to authenticate communication between two or more parties, like websites and browsers. They are a type of X.509 certificate and are usually encoded in the DER (Distinguished Encoding Rules) or PEM (Privacy Enhanced Mail) format.

The main challenge with CER files is that they are not widely supported by most software applications. To convert a CER file, you will need to use specific software such as OpenSSL, GnuPG, or Microsoft Certificate Services. These tools can convert CER files to other formats such as PEM, DER, PFX, and P7B.

It is important to note that CER files are not always easy to convert. Depending on the type of certificate, the conversion process can be complex and require a high level of technical knowledge. Additionally, some CER files may not be compatible with certain software applications, making conversion difficult.

For these reasons, it is often easier and more reliable to use an online service such as Convert.Guru to convert CER files. Convert.Guru is free and easy to use, and can convert CER files to a wide range of formats, including PEM, DER, PFX, and P7B.

The CER Converter Story

The history of Convert.Guru began more than 25 years ago in California, when Tom Simondi published the most comprehensive database of file formats on his website. Before that, Tom had worked on Space Shuttle development at the Air Force Systems Command’s Space Division in Los Angeles. He is known as one of the top programmers of the late 1980s.

When Microsoft integrated Tom’s Filext database into Windows XP, it became the leading platform for analyzing and processing file types and formats.

Today, we use the latest technologies to analyze, process, and convert one of the world's largest collections of file formats. We are committed to developing the best CER converter by continuously improving quality, usability, and reliability.