Certificate Converter
Convert certificates between different formats. Files and passwords are sent to our server for processing. Use test certificates when a file contains a private key.
Select the certificate file you want to convert. Make sure it matches the input format you select below.
Select the format of your input certificate file.
Select the desired output format for your certificate.
Required for PFX/P12 formats. Leave empty if your certificate is not password-protected.
Using Certificate Format Converter for open banking
Convert certificate files between PEM, DER and PKCS#12 container formats.
Sandbox example and expected result
Use a disposable sandbox certificate to convert DER to PEM and compare the subject and serial number.
Limitations and troubleshooting
Conversion does not renew a certificate or establish trust. PFX/P12 containers can contain private keys; use non-production material and check the resulting contents.
Where your input is processed
Files and any entered container password are sent to our server for conversion. Use synthetic test data.
Maintained by OpenFinanceTools. Guidance updated 23 October 2026. Testing and editorial approach