# typepki-asn1parse

> ASN.1 parser utility for TypePKI library (beta)

Latest version **0.8.0** (published 2026-01-08) · MIT license · 0 weekly downloads

## Install

```sh
npm install typepki-asn1parse
pnpm add typepki-asn1parse
yarn add typepki-asn1parse
bun add typepki-asn1parse
```

## Health

**Score 50/100 (C)** — status: stable.

Positive: esm support; no vulnerabilities.

Warnings: low downloads; no types; pre 1.0.

## Facts

| | |
|---|---|
| Version | 0.8.0 |
| Published | 2026-01-08 |
| First published | 2024-05-16 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | none |
| Module format | ESM + CommonJS |
| Dependencies | 2 |
| Unpacked size | 60.7 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| Author | Kenji Urushima |
| Maintainers | kjur |
| Keywords | asn1, x680, x690, der, ber, parser |

## Links

- npm: https://www.npmjs.com/package/typepki-asn1parse
- Repository: https://github.com/kjur/typepki-asn1parse
- Homepage: https://kjur.github.io/typepki-asn1parse
- Issues: https://github.com/kjur/typepki-asn1parse/issues
- npm.io page: https://npm.io/package/typepki-asn1parse

## Dependencies (2)

- [typepki-oiddb](https://npm.io/package/typepki-oiddb.md) ^0.4.1
- [typepki-strconv](https://npm.io/package/typepki-strconv.md) ^0.6.0

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## Recent versions

- 0.8.0 (latest) — 2026-01-08
- 0.7.3 — 2024-07-06
- 0.7.2 — 2024-07-06
- 0.7.1 — 2024-07-05
- 0.7.0 — 2024-06-22
- 0.6.1 — 2024-06-16
- 0.6.0 — 2024-06-12
- 0.4.0 — 2024-05-22
- 0.3.0 — 2024-05-22
- 0.2.1 — 2024-05-20
- 0.2.0 — 2024-05-20
- 0.1.0 — 2024-05-16

## README

typepki-asn1parse: ASN.1 parser utility for TypePKI library
===========================================================

[TOP](https://kjur.github.io/typepki-asn1parse/) | [github](https://github.com/kjur/typepki-asn1parse) | [npm](https://www.npmjs.com/package/typepki-asn1parse) | [TypePKI](https://kjur.github.io/typepki/) 

The 'TypePKI' library is an opensource free TypeScript PKI library which is the successor of the long lived [jsrsasign](https://kjur.github.io/jsrsasign) library.

The 'typepki-asn1parse' is a ASN.1 parser utility for TypePKI library. 

## FEATURE
- ASN.1 DER parser for ASN.1 hexadecimal string (BER will also be in the future.)
- Dual CommonJS/ES module package supporting CommonJS(CJS) and ES modules

## Usage
``` JavaScript
import { asn1parse } from "typepki-asn1parse";
console.log(asn1parse("300602010a02010b"));
```
This shows
```
{
  "t": "seq",
  "v": [
    { "t": "int", "v": "0a" },
    { "t": "int", "v": "0b" },
  ]
}
```

## Parser output
Result will be a Record object which has following members:

- t - short ASN.1 tag name
- v - ASN.1 value

## short ASN.1 tag name

|short name|ASN.1 name|code|value|value sample|
|----------|----------|----|-----|------------|
|bool|INTEGER|01|||
|int|INTEGER|02|||
|bitstr|BitString|03|||
|octstr|OctetString|04|||
|null|NULL|05|||
|oid|ObjectIdentifier|06||{oid: "0.2.3.15"}|
|enum|Enumerated|0a|||
|utf8str|UTF8String|0c||{str: "りんご3"}|
|prnstr|PrintableString|13||{str: "test12"}|
|ia5str|IA5String|16||{str: "u1@example.com"}|
|utctime|UTCTime|17||131231235959Z|
|gentime|GeneralizedTime|18||20131231235959Z|
|seq|SEQUENCE|30|array of Record|[{t:"int",v:"0123"}]|
|set|SET|31|array of Record|[{t:"int",v:"0123"}]|

## Encapsulated
When the ASN.1 value is a ASN.1 TLV or a sequence of ASN.1 TLV, the V will also be parsed.

This will be applied to ASN.1 application tag TLV such as "[0]" or "[1]".

---
_Source: https://npm.io/package/typepki-asn1parse · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._