ASN.1 Decoder

Note - Nov 2022: there is a better version of this tool posted at ldh.org/asn1.html that lists more OIDs, does recursive decoding of OCTETSTRING and tries to interpret most things as ascii. This tool remains posted just to support people that already link here. I suggest you use the improved tool.


Input
Output

OIDs
ASN.1 Decoder by: manaslu_eiger@yahoo.co.jp
Original from: www.geocities.co.jp/SiliconValley-SanJose/3377/asn1JS.js
I've made some changes.

Input can be: 30 03 02 01 ff (HEX string) 30030201ff (HEX string, without space) 30 03 02 01 FF (HEX string, upper case) 30030201FF (HEX string, without space, upper case) MAMCAf8= (BASE64/PEM)

Carriage-returns, line-feeds, and tab will be ignored as white space.

Each HEX token must be two digits. I.E. use 03 instead of 3.

OID: 06092A864886F70D010105 CERT: MIIHTzCCBTegAwIBAgIJAKPaQn6ksa7aMA0GCSqGSIb3DQEBBQUAMIGuMQswCQYD VQQGEwJFVTFDMEEGA1UEBxM6TWFkcmlkIChzZWUgY3VycmVudCBhZGRyZXNzIGF0 IHd3dy5jYW1lcmZpcm1hLmNvbS9hZGRyZXNzKTESMBAGA1UEBRMJQTgyNzQzMjg3 MRswGQYDVQQKExJBQyBDYW1lcmZpcm1hIFMuQS4xKTAnBgNVBAMTIENoYW1iZXJz IG9mIENvbW1lcmNlIFJvb3QgLSAyMDA4MB4XDTA4MDgwMTEyMjk1MFoXDTM4MDcz MTEyMjk1MFowga4xCzAJBgNVBAYTAkVVMUMwQQYDVQQHEzpNYWRyaWQgKHNlZSBj dXJyZW50IGFkZHJlc3MgYXQgd3d3LmNhbWVyZmlybWEuY29tL2FkZHJlc3MpMRIw EAYDVQQFEwlBODI3NDMyODcxGzAZBgNVBAoTEkFDIENhbWVyZmlybWEgUy5BLjEp MCcGA1UEAxMgQ2hhbWJlcnMgb2YgQ29tbWVyY2UgUm9vdCAtIDIwMDgwggIiMA0G CSqGSIb3DQEBAQUAA4ICDwAwggIKAoICAQCvAMtwNyuAWko6bHiUfaN/Gh/2NdW9 28sNRHI+JrKQUrpjOyhYb6WzbZSm891kDFX29ufyIiKAXuFixrYp4YFs8r/lfTJq VKAyGVn+H4vXPWCGhSRv4xGzdz4gljUha7MI2XAuZPeEklPWDrCQiorjh40G072Q DuKZoRuGDtqaCrsLYVAGUvGef3bsyw/QHg3PmTA9HMRFEFis1tPo1+XqxQEHd9ZR 5gN/ikilTWh1uem8nk4ZcfUyS5xtYBkL+8ydddy/Js2Pk3g5eXNeJQ7KXOt3EgfL ZEFHcpOrUMPrCXZkNNI5t3YRCQ12RcSprj1qr7V9ZS+UWBDsXHyvfuK2GNnQm05a Sd+pZgvMPMZ4fKecHePOjlO+Bd5gD2vlGts/4+EhySnB8esHnFIbAURRPHsl18Tl UlRdJQfKFiC4reRB7noI/plvg6aRArBsNlVq5331lubKgdaX8ZSD6e2wsWsSaR6s +12pxZjptFtYer49okQ6Y1nUCyXeG0+95QGezdIp1Z8XGQpvvwyQ0wlf2eOKNcx5 Wk0ZN5K3xMGtr/R5JJqyAQuxr1yW84Ay+1w9mPGgP0revq+ULtlVmhduYJ1jbLhj ya6BXBg14JC7vjxPNyK5fuvPnnchpj04gftI2jE9K+OJ9dC1vX7gUMQSibMjmhAx hduub+84Mxh2EQIDAQABo4IBbDCCAWgwEgYDVR0TAQH/BAgwBgEB/wIBDDAdBgNV HQ4EFgQU+SSsD7K1+HnA+mCIG8TZTQKeFxkwgeMGA1UdIwSB2zCB2IAU+SSsD7K1 +HnA+mCIG8TZTQKeFxmhgbSkgbEwga4xCzAJBgNVBAYTAkVVMUMwQQYDVQQHEzpN YWRyaWQgKHNlZSBjdXJyZW50IGFkZHJlc3MgYXQgd3d3LmNhbWVyZmlybWEuY29t L2FkZHJlc3MpMRIwEAYDVQQFEwlBODI3NDMyODcxGzAZBgNVBAoTEkFDIENhbWVy ZmlybWEgUy5BLjEpMCcGA1UEAxMgQ2hhbWJlcnMgb2YgQ29tbWVyY2UgUm9vdCAt IDIwMDiCCQCj2kJ+pLGu2jAOBgNVHQ8BAf8EBAMCAQYwPQYDVR0gBDYwNDAyBgRV HSAAMCowKAYIKwYBBQUHAgEWHGh0dHA6Ly9wb2xpY3kuY2FtZXJmaXJtYS5jb20w DQYJKoZIhvcNAQEFBQADggIBAJASryI1wqM58C7e6bXpeHxIvj99RZJe6dqxGfwW PJ+0W2aeaufDuV2I6A+tzyMP3iU6XsxPpcG1Lawk0lgH3qLPaYRgM+gQDROpI9CF 5Y57pp49chNyM/WqfcZjHwj0/gF/JM8rLFQJ3uIrbZLGOU8W6jx+ekbURWpGqOt1 glanq6B8aBMz9p0w8G8nOSQjKpD9kCk18pPfNKXG9/jvjA9iSnyu0/VU+I22mlaH FoI6M6taIgj3grrqLuBHmrS1RaMFO9ncLkVAO+rcf+g769HsJtg1pDDFOqxXnrN2 pSB7+R5KBWIBpih1YJeSDW4+TTdDDZIVnBgizVGZoCkaPF+KMjNbMMeJL0eYD6MD xvbxrN8y8NmBGuScvfaAFPDRLLmF9dijscilIeUcE5fuDr3fKanvNFNb0+RqE4QG tjICxFKuItLcsiFCGtpA8CnJ7AoMXOLQusxI0zcKzBIKinmwPQN/aUv0NCB9szTq jktk9T79syNnFQ0EuPAtwQlRPLJsFfClI9eDdOTlLsn+mCdCxqvGnrDQWzilm1De fhiYtUU79nm06PcaewaD+9CL2rvHvRirCG88gGtAPxkZumWK5r7VXNM21+9AUiRg OGcEMeyP84LG3rlV8zsxkVrctQgVrXYlCg17LofiDKYGvCYQbTed7N14jHyAxfDZ d0jQ

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