Yoonadev

Certificate Workbench

Certificate ↔ Key Matcher

Check certificate & key pair

Check whether a certificate and Private Key belong to the same key pair locally.

🔒 Local-only · No upload · No storage

Try an example

TEST ONLY · Public synthetic examples. Never use these keys for real services.

Paste a certificate beginning with -----BEGIN CERTIFICATE-----.

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🔒 Private Keys never leave this browser.

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Advanced information / extensions

Inputs and results are cleared when edited, cleared or when leaving this page. Copy and file saving happen only when you request them.

PEM text only · up to 1 MiB, 20 blocks, 128 KiB per block. DER, PFX/PKCS#12, JKS and encrypted keys are not supported in v1.

RSA PKCS#8 / PKCS#1 and EC PKCS#8 / SEC1 (named P-256, P-384, P-521). Encrypted keys are not supported.

Usage guideWhen to use · How to use · Understand results

When to use this tool

Identify which private key belongs to a certificate when replacing a server certificate or recovering a configuration.

How to use it

  1. Supply certificate PEM and the private-key PEM in their separate input fields.
  2. Run the key-pair check and read the match, mismatch or unsupported-format result.

Reading the result

The local check compares public material and verifies a signature challenge. A match does not establish certificate trust or expiry suitability. The key is processed in browser memory.

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