PEM Parser

Parse and analyze PEM-encoded data.

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Input
Output
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About pem parser

PEM Parser needs nothing from a server once the page has loaded. Leave it open on a train with no signal and it carries on.

Paste a customer record into it if you need to. The record never leaves the machine you are sitting at.

You will find it under Keys & certificates, alongside 7 other tools for the same sort of job.

Identifies key types (RSA, EC, X.509), formats (PKCS#1, PKCS#8, SPKI), and displays size and hex preview.

How to use it

01
Start it
Every control is on the tool itself. Keyboard shortcuts, where there are any, are listed beside it.
02
Watch it run
It updates in the page as you go. Nothing is sent anywhere, so it keeps working with the network off.
03
Close when done
Nothing is stored between visits. Reloading gives you a clean start rather than picking up where you left off.

Examples

Parse PEM Block
Analyze a PEM-encoded public key to identify its type and size
Input
-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAzbcx4tfj8K+lXzGe7ihp
UO8AZSKtTIWOQIEeCYQjnoxv0GGBr9GU9viLZXvUdDi4weZkoyXBJGbdLsW2Otpo
tcsMUk2MRzxE61BB3QUJBlIK8h4SjmHGrrwQFbo48fKnDr7I/sk17TRmil94d6hA
sGhyyoJOqlQp4gJ5tRZpdwwzYNvMOm7jjYkTyTQ2q+Jyw1DDemwi0GRrtuB3ciD0
Ogl/B8lU8uekK8vq2iDiLXH6JWL997lLNJJBr/oH7NbhbpNDR2DZ7VA4lUyPNDBs
Xn99uVFw0ueo7SrlOe1Zuz7XQy1xdorISLfp4ZFUk5Iaf0JykysJLUA4u0lJ+SUF
VwIDAQAB
-----END PUBLIC KEY-----
Output
=== PEM Block 1 ===
Type: PUBLIC KEY
Size: 294 bytes (2352 bits)
Base64 length: 392 characters
Format: SPKI (Subject Public Key Info)
First bytes: 30 82 01 22 30 0d 06 09 2a 86 48 86 f7 0d 01 01 01 05 00 03 82 01 0f 00 30 82 01 0a 02 82 01 01 ...

Questions

Does PEM Parser work offline?+

Yes. It is JavaScript running in this tab, so once the page has loaded it needs nothing further from the network. Put the machine in flight mode and it carries on. Nothing you do here is sent anywhere, because there is nowhere for it to go.

Does it remember anything between visits?+

No. Reload the page and it starts from nothing. There is no account, no saved state and no cookie holding your last session. That is a deliberate trade: it cannot lose your data because it never keeps any.

Is it accurate?+

Timing comes from performance.now(), the high resolution clock the browser provides, rather than from setInterval, which drifts by a few milliseconds every tick and compounds over minutes. What can still shift things is the browser throttling a tab in the background, so leave it visible if the timing matters.

Does it make a sound?+

Where a sound makes sense, it is generated with the Web Audio API rather than loaded as a file, so there is nothing to download and nothing to block. Browsers refuse to start audio until you have interacted with the page, which is why the first press is what switches it on.

Can I use PEM Parser on a phone?+

Yes. The controls are sized for touch and the layout collapses to one column on a narrow screen. Bear in mind that a phone locking its screen will suspend the page, and timing stops with it.