Frequently Asked Questions

Q: Should I select the "Convert files offline instead of online" option? NEW!

A: There's a new "Convert files offline instead of online" option below the conversion button. This option works on most image, video and audio formats, it doesn't work on document formats yet. If this option is selected, your files will be converted offline by Javascript or WebAssembly in web browser on your local device. WebAssembly is a type of code that can be run in modern web browsers - it is a low-level assembly-like language with a compact binary format that runs with near-native performance and provides languages such as C/C++, C# and Rust with a compilation target so that they can run on the web. It is also designed to run alongside JavaScript, allowing both to work together.

Note that the offline converter only works on web browsers that support new technologies such as ES Modules, WebAssembly, Shared Array Buffer and Site Isolation. We recommend using the latest web browsers and operating systems.

This option is unselected by default, you should select it if:

  • Your file's file size is larger than 200mb.
  • Your file contains sensitive data and you don't want it to be uploaded to any online servers.
  • All currently allocated online servers are 100% occupied.
Q: What is cdkm.com?

A: Cdkm.com is our next-generation online converter built with many cutting-edge open-source projects. Cdkm.com is dedicated to converting files in the easiest way. All file uploads, conversions and downloads can be completed in one single webpage regardless of file formats.

Q: Why choose cdkm.com?

A: Here are top reasons why you should choose cdkm.com:

  • 100% free guaranteed for both personal and commercial uses. No need to sign up for an account.
  • All file uploads, conversions and downloads can be completed in one single webpage regardless of file formats. No need to switch webpages.
  • Cdkm.com takes a number of steps to secure your files. Upload, convert and delete, no files left behind.
  • Cdkm.com is built with many cutting-edge open-source projects such as Ghostscript, LibreOffice and FFMpeg.
  • Converting files on cdkm.com is as simple as 1-2-3. Choose file, choose output format and click button to start conversion.
  • Minimalist website design without any redundant items.
  • Mobile-first design to create better experiences on small screen of mobile phone.
  • One-click to pack all output files or delete all output files to protect your privacy.
Q: Is cdkm.com secure?

A: Yes, we take a number of steps to secure your files. Here are a few of the most prominent:

  • All traffic from and to our servers is secured by transport level security (TLS) using 128 bit SSL to encrypt the data sent between your systems and ours.
  • All of our hardware runs in world-class, highly secure data centers utilizing state-of-the art electronic surveillance and multi-factor access control systems.
  • Your files will be saved to a private directory with random characters. Your files are only temporarily stored on our servers for up to 2 hours, after that they will be automatically deleted by a scheduled program. You can also delete all your files by yourself anytime.
Q: How to convert files on cdkm.com?

A: Converting files on cdkm.com is as simple as 1-2-3.

  • 1. Choose local files on your local device or enter the URL of an online file.
  • 2. Choose a target format and set conversion options if needed.
  • 3. Click the "START CONVERSION" button and wait for conversion to complete. The output files will be listed in the same webpage.
Q: What file formats does cdkm.com support?

A: You can check supported file formats at https://cdkm.com/format. Please note this is just a small list of file formats supported by cdkm.com, many unpopular file formats supported are not listed. For example, cdkm.com supports hundreds of image formats while only the top popular image formats are listed. You can directly convert these unpopular formats on cdkm.com without any problems.

Q: What platforms does cdkm.com support?

A: You can use cdkm.com on any operating system (such as Windows, Linux, Mac OS, Android or iOS) that has a web browser. Because the service is provided online and there are no software downloads needed.

Q: What are the conversion limitations?

A: You can choose up to 10 files each time, each file size can be up to 40mb for documents or 200mb for other formats. Each file conversion takes up to 10 minutes to finish. Conversion will be automatically terminated if time is up. The conversion limitations may change occasionally based on server overloads.

Q: What does "Always use open-source projects to convert documents" option mean?

A: Although all files can be converted by open-source projects, we reserved some conversions processed by the developers' official software. For example, your Word, Excel or PowerPoint files will be converted by Microsoft Office Word, Excel or PowerPoint software by default. If the "Always use open-source projects to convert documents" option is checked, your files will be converted by LibreOffice software instead of Microsoft Office. Check more information on conversion options.

Q: How can I download output files if I accidentally closed the conversion page?

A: The history page shows all output files in case you closed the conversion page by accident before downloading files. The history file list is stored as "Local Storage" in your web browser only, it will not be exposed outside of your current web browser. You can remove history by clicking the "Delete all files" button which can be found in most pages.

Q: Why did my conversion fail?

A: Most conversion failures are caused by server overload. The allocated server's CPU or memory is currently 100% occupied so it doesn't have enough resources to complete your conversion. You can try it again a few minutes later if this happens. There are also many other reasons that may cause conversion failure, for example: the source file is not supported, corrupted, encrypted with password or Digital Rights Management (DRM). If your conversion fails, you can click the "Why it failed?" button next to your file to check out the exact reason.

Q: How can I download all output files in one ZIP file?

A: To download all output files in one ZIP file, simply click the "Compress all files" button in the "OUTPUT FILES" section. It will create two ZIP files if the files were converted on both Windows and Linux servers.

Q: How can I delete all my files?

A: To delete all your files, simply click the "Delete all files" button in the "OUTPUT FILES" section. All your files will be deleted immediately and can't be recovered. If you don't click the "Delete all files" button, your files will be automatically deleted by a scheduled program within 2 hours.

Q: I have more questions, who should I write to?

A: Please send your additional questions to support@cdkm.com and will usually get a response in one business day if it's question about file conversion, other questions may be ignored.