Open-source alternatives to Utf8Json

Push based .NET Streams

Kryo is a Java binary serialization framework and object cloning library used to convert Java objects into a compact binary format and restore them from bytes. It provides a system for creating deep or shallow copies of complex object graphs without requiring binary conversion. The project utilizes variable-length integer encoding and integer-ID class registration to reduce the size of serialized data. It handles complex object graphs through circular reference tracking to prevent data duplication and infinite loops. To maintain long-term data viability, it includes schema evolution managemen

EDI Serializer/Deserializer. Supports EDIFact, X12 and TRADACOMS formats

A declarative serialization framework for controlling formatting of data at the byte and bit level using field bindings, converters, and code.

C library/compiler for the Cap'n Proto serialization/RPC protocol

CsvHelper is a library for reading and writing comma-separated value files by mapping data to custom class objects. It functions as a parsing library and data mapper that converts flat-file text into structured data objects and serializes internal data sets back into standard CSV files. The project emphasizes memory efficiency through a parser that optimizes resource consumption. It utilizes field value caching and an interned string cache to store repetitive values, which reduces memory overhead when processing large datasets. The library provides a configuration-driven parsing engine that

Fast .NET JSON (De)Serializer, Built On Sigil

Binary Serialization

Netstring for C

MPack - A C encoder/decoder for the MessagePack serialization format / msgpack.orgC

A Java library for serializing objects as PHP serialization format.

protobuf-net is a binary serialization framework and .NET library that implements the Protocol Buffers specification. It functions as a schema-based serialization tool and contract-first data mapper, converting complex object graphs into a compact binary format for storage and network transmission. The library enables cross-platform data exchange and high-performance networking by reducing payload sizes and processing time. It specifically supports object hierarchy persistence, allowing the serialization and reconstruction of complex class structures that include inheritance and derived types

Bond was a cross-platform framework for working with schematized data. The open-source project ended on March 31, 2025.

MessagePack implementation for C and C++ / msgpack.orgC/C++

MessagePack implementation for Common Language Infrastructure / msgpack.orgC#

MessagePack serializer implementation for Java / msgpack.orgJava

MessagePack-CSharp is a high-performance binary serialization library for .NET applications that converts object graphs into the MessagePack format. It functions as a C# data serialization toolkit and a polymorphic binary encoder capable of handling abstract classes and interfaces using union keys to identify concrete derived types. The library provides a binary format transcoder to transform binary data into human-readable JSON for debugging. It supports ahead-of-time formatter generation to avoid runtime overhead and implements LZ4 binary compression to reduce the size of serialized data.

Infinitely Fast Deserializer for .NET, .NET Core and Unity.

Protocol Buffers implementation in C

Simple Binary Encoding (SBE) - High Performance Message Codec

Schema.org objects turned into strongly typed C# POCO classes for use in .NET. All classes can be serialized into JSON/JSON-LD and XML, typically used to represent structured data in the head section of html page.