ASN.1 Tools for C#


The OSS® ASN.1 Tools for C# is a powerful development toolkit that helps developers rapidly build applications using ASN.1. The toolkit includes the following:

  • A powerful ASN.1 to C# compiler, which supports the latest version of the ASN.1 standards
  • A runtime DLL with ASN.1 BER, DER, PER/UPER, CPER/CUPER, XER, CXER, E-XER, OER, COER, and JSON encoder/decoder engines
  • A number of utilities to simplify and speed up your development
High Performance

The ASN.1 compiler for C# takes ASN.1 schemas as input and generates C# language classes. In addition to core functionalities, the OSS ASN.1/C# compiler offers extensive diagnostic capabilities to minimize your development time and effort.

Support for
Partial Decoding

A runtime DLL provides ASN.1 encoding and decoding functions and auxiliary functions to operate on application messages.

Support for

Our ASN.1 products support LTE Advanced Pro including NB-IoT, C-V2X and LTE-M. OSS products support the 3GPP 5G specifications.

Compatible with
.NET Core, UWP, and Xamarin

The ASN.1 compiler for C# and the runtime library support the JSON Encoding Rules, which allow you to serialize ASN.1 data to the popular JSON format and convert between JSON messages and ASN.1 binary messages.

Support for

The ASN.1 compiler for C# and the runtime library also support the Octet Encoding Rules, which allow you to work with ASN.1 binary messages that can be encoded/decoded significantly faster than BER and PER messages, while being only slightly less compact than PER messages.

Support for E-XER allows you to generate XML compatible with output from XML Schema tools.

  • Backward compatibility guaranteed
  • ASN.1 Studio, an intuitive IDE for ASN.1 schema editing and message analysis
  • Support for partial decoding
  • Large INTEGERs (for cryptographic applications, no upper or lower bounds)
  • Encoding of extensible types (unknown extensions)
  • Rich set of C# representations for ASN.1 types
  • Automatic decoding for any kind of constraint
  • Contents constraints (full support)
  • No implementation restrictions; never rewrite your ASN.1 to accommodate encoding limitations
  • File and socket support
  • Concatenated PDU support
Standards Conformance

Our ASN.1 compiler for C# and ASN.1 encoders/decoders are fully compliant with all ASN.1 standards. We support: 2021, 2015, 2008, 2002, 1997, 1994, and 1990. For a complete list, see the Standards Conformance page.

Free Trial

Download the ASN.1/C# Tools today!

24x7 Tech Support


We are here: 24 hours a day, 7 days a week.

  • Phone: 1-888-OSS-2761 (USA and Canada)
  • Phone: 1-732-302-9669 (International)
  • Fax: 1-732-302-0023
  • Email:

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