24/7 Validation Support · Certificates issued in minutes
0
Sign In
FREE ONLINE SSL TOOL

SSL Certificate Format Converter

Convert SSL certificates and private keys between PEM, DER, PKCS#7 (P7B), and PKCS#12 (PFX) formats instantly. Prepare your certificates for Microsoft IIS, Apache, Nginx, Tomcat, or Exchange with 100% client-side privacy.

Convert SSL Certificate
Conversion Guide

Client-Side Zero-Knowledge

All certificate conversions and PFX encryptions happen locally inside your browser. No files are uploaded to our servers.

Universal Format Support

Supports PEM, DER, PKCS#7 (P7B), and PKCS#12 (PFX) in both directions with password protection.

Ready for Any Web Server

Outputs standard files for Microsoft IIS, Windows Server, Apache, Nginx, Tomcat, and Java Keystores.

ONLINE SSL CONVERSION ENGINE

Convert Between SSL Formats

Select your conversion direction, paste or upload your certificate files, and download the converted output.

Primary Certificate (.crt / .pem)*
Private Key (.key)*
CA Bundle / Intermediate Certificates (Optional)
Required by Windows IIS during PFX import
Identifies certificate in Windows Certificate Manager
Conversion completed successfully! Download your converted certificate below.
SSL GUIDE & BEST PRACTICES

Understanding SSL Certificate Formats

Which format does your web server need? Learn the key differences between PEM, DER, PFX, and P7B.

1. PEM & DER Formats

PEM is the most common format (.crt, .pem, .key), using Base64 ASCII text. It is used by Apache, Nginx, and Linux servers. DER is the binary encoding of PEM, commonly required by Java platforms and Windows environments.

2. PKCS#12 (PFX) for Windows

PFX (PKCS#12) is a password-protected binary archive that bundles your SSL Certificate, Private Key, and Intermediate CA chain into a single .pfx or .p12 file. It is the mandatory format for Microsoft IIS and Tomcat.

3. PKCS#7 (P7B) Bundles

P7B (PKCS#7) contains only public certificates and certificate chains—it never contains private keys. Windows Server and Tomcat often use P7B files to import complete CA chains without risk of key exposure.

FREQUENTLY ASKED QUESTIONS

SSL Converter FAQs

Common questions regarding certificate formats, server compatibility, and conversion security.

Microsoft IIS requires the PKCS#12 (.pfx or .p12) format. Use our ‘PEM to PFX’ conversion mode, provide your Certificate (.crt) and Private Key (.key), set a password, and import the resulting .pfx file into IIS Manager under Server Certificates.
Select the ‘PFX to PEM’ conversion mode, upload your .pfx file, and type your decryption password. Our tool will immediately extract the Certificate (.crt), Private Key (.key), and CA chain as separate PEM files for Nginx or Apache.
Yes, 100% safe. All conversions and cryptographic operations run exclusively inside your browser sandbox using Node-Forge. Your private keys never leave your device memory and are never uploaded to any server.
PKCS#12 is an industry-standard secure archive format that encrypts the embedded private key using Triple-DES or AES. The password is required to encrypt the key during generation and decrypt it during server import.
Both .crt and .pem usually contain the same Base64 encoded ASCII text beginning with ‘—–BEGIN CERTIFICATE—–‘. The .crt extension is common on Windows and Debian/Ubuntu, while .pem is common on Red Hat/CentOS and Unix systems.

Looking for Genuine Commercial SSL Certificates?

RenewalSSL provides trusted SSL certificates from Sectigo, DigiCert, and GeoTrust with instant delivery, free reissues, and dedicated technical support.

Browse SSL Certificates
Generate New CSR

The premier marketplace for seamless SSL certificate issuance, renewal, and website trust management worldwide.

Global Certificate Distribution Hub
Support: support@renewalssl.com

Resources & Support

Knowledge Base & Guides
CSR Generator Guide
Contact Support Team
Client Portal Login
View Shopping Cart
Quick Checkout

© 2026 RenewalSSL.com. All rights reserved.

0
Sign In

SiteLock

Scan for malware, remove threats, and protect your website automatically.

TrustedSite

Display trust seals. Boost conversions with real-time security verification.

CodeGuard

Daily automatic backups. Restore your website instantly after data loss.

Overview

Next-gen PKI platform. Manage digital trust at enterprise scale.

Trust Lifecycle

Automate the full certificate lifecycle. Stay secure and compliant.

CertCentral TLS

Simplify certificate lifecycle management across your entire network.

IoT Trust

Automate the full certificate lifecycle. Stay secure and compliant.

Software Trust

Protect software supply chains. Ensure secure code delivery.

Document Trust

Digitally sign and validate documents. Preserve integrity and origin.

Mark Certificates

Enable verified brand logos in emails. Boost recognition and trust.

ACME

Automate SSL certificate issuance, installation, and renewal effortlessly.

AutoInstall SSL™

Automate SSL installation and renewal. Prevent expiration and downtime.

Social Media

Facebook X-twitter Instagram Envelope