Does this tool decrypt encrypted private keys?

No. The tool identifies that encryption is present (e.g. PKCS#8 EncryptedPrivateKeyInfo or Proc-Type headers) but does not ask for passwords or attempt brute-force decryption.

What is the difference between PKCS#1 and PKCS#8?

PKCS#1 is specific to RSA keys (marked with "-----BEGIN RSA PRIVATE KEY-----"), while PKCS#8 is a generic standard capable of representing any cryptographic algorithm (marked with "-----BEGIN PRIVATE KEY-----").

What is the difference between RSA and Ed25519 keys?

RSA relies on integer factorization and uses larger key sizes (typically 2048 to 4096 bits) for security. Ed25519 is an Edwards-curve Digital Signature Algorithm offering superior performance, tiny 256-bit key sizes, and better resistance to side-channel attacks.

Can this tool read single-line OpenSSH public keys like id_ed25519.pub?

Yes. It recognizes OpenSSH public key strings (starting with ssh-rsa, ssh-ed25519, or ecdsa-sha2-nistp256), extracts the key comment, and computes the canonical SHA-256 fingerprint.

What is a SubjectPublicKeyInfo (SPKI) header?

SPKI is the standard X.509 ASN.1 structure that wraps a public key along with an algorithm identifier OID (Object Identifier), commonly marked with "-----BEGIN PUBLIC KEY-----".

How do I verify the SHA-256 fingerprint against an SSH server?

Compare the SHA-256 fingerprint generated by this tool with the output of "ssh-keygen -lf /path/to/key.pub" on your terminal. They should match identically.

developer-tools100% Client-Side LocalSecurity

PEM Key Inspector

Inspect PEM-encoded keys locally in your browser. Identify key type, algorithm, format, key size and supported curve information without uploading private key material.

Privacy Guarantee: Processing happens locally in your browser. Your PEM data is not uploaded to SPAUL Hub. Private key material is never logged, stored in localStorage, or transmitted.

Zero-Upload Cryptographic Privacy: Your PEM data is processed strictly in your local browser memory using native Web Crypto APIs. Sensitive private keys are never transmitted, logged, or saved to localStorage.

Paste PEM Key / Certificate

Samples:

How to Use

Paste your PEM-encoded public key, private key, X.509 certificate, or OpenSSH key into the editor.

Review automatically identified parameters: algorithm (RSA, ECDSA, Ed25519), bit length, and elliptic curve.

Check the SHA-256 DER fingerprint to verify key identity against server logs or cloud infrastructure.

Inspect public exponents and SPKI structure without exposing raw private key material.

Copy the detailed cryptographic audit summary or download an offline inspection log.

Why Use PEM Key Inspector?

Zero-Upload Privacy Assurance

Cryptographic material never leaves your device. Private keys are never logged, stored, or sent over the internet.

Wide Format Recognition

Supports PKCS#1, PKCS#8, SubjectPublicKeyInfo, X.509 certificates, and single-line OpenSSH keys.

Algorithm & Curve Detection

Accurately determines RSA key sizes (2048, 3072, 4096-bit) and EC curves (P-256, P-384, P-521, secp256k1).

Encrypted Key Warning

Clearly alerts users when password-encrypted private key material is detected.

About This Tool

The PEM Key Inspector decodes and analyzes PEM-formatted cryptographic keys, certificates, and CSRs directly within client-side browser memory. It inspects ASN.1 structures and SPKI headers to identify key algorithms (RSA, ECDSA, Ed25519), bit lengths, elliptic curves, and SHA-256 fingerprints with zero server transmission.

Tags:#PEM key inspector#PEM key parser#PEM key viewer#PEM key decoder#inspect PEM key#private key inspector#public key inspector

Frequently Asked Questions

All parsing occurs strictly in your local browser sandbox using native Web Crypto APIs. However, as an industry best practice, never paste active production private keys into any browser utility.

Companion Guides & Technical Insights

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Security & PrivacyOctober 1, 2026

Is It Safe to Paste API Keys Into Online Tools? Local Processing Explained

Learn why you should avoid pasting API keys, private keys and sensitive data into untrusted online tools, and how local browser processing can reduce unnecessary data exposure.

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