# neuecc/Utf8Json

Definitely Fastest and Zero Allocation JSON Serializer for C#(NET, .NET Core, Unity, Xamarin).

Repository: https://github.com/neuecc/Utf8Json
Canonical: https://ross.abutalabs.com/products/utf8json
Language: C#
License: MIT
License Family: permissive
Archived: true
Last push: 2022-05-16T05:46:16+00:00

## Health v2 (maintenance only)
Score: 10/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 3272, "days_push": 1570, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: archived
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2382, forks 269 (observed 2026-08-28T04:06:42.370050+00:00)

## What it is
Utf8Json is a high-performance, zero-allocation JSON serializer for C# that reads and writes directly to UTF8 binary, targeting .NET, .NET Core, Unity, and Xamarin. The project is now archived, and users are directed to a community fork.

## Use cases
- serialize objects to json in c#
- fastest json serializer for .net
- zero allocation json serialization
- json serializer for unity
- convert objects to utf8 json bytes
- high performance json parsing in c#

## When to choose
- you need maximum JSON serialization throughput in .NET or Unity with minimal allocations
- you write directly to UTF8 streams or byte arrays and want to avoid encoding overhead

## When to avoid
- you want an actively maintained library - the project is archived and a community fork is recommended
- you need UTF16 string-based serialization or broad modern .NET feature support

## Facets
- artifact type: library
- maturity: abandoned
- function: serialization, json
- domain: developer-tools, web-development, performance
- platform: dotnet, cross-platform
- tags: json-serializer, zero-allocation, utf8, unity, xamarin, archived

## Member repositories
- neuecc/Utf8Json (main) score 10

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:06:42.370050+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T02:34:43.451094+00:00, confidence not recorded.
  - readme: https://github.com/neuecc/Utf8Json (fetched 2026-08-28T04:06:42.370050+00:00, sha cb2469f82f25)
- Data as of 2026-08-30T08:39:29.467469+00:00.