---
id: pysimdjson
version: "7.0.2"
license: unclear
license_treatment: unclear
maintenance: aging
---

# pysimdjson — Add your description here

License: unclear · Maintenance: aging · Downloads: 1.5M/mo

## What it is and what it does

pysimdjson is a Python wrapper around a SIMD-accelerated JSON parser. When SIMD instructions are available on the host platform, parsing is accelerated; on systems without SIMD support, the library automatically falls back to a standard parser, ensuring compatibility everywhere. The package is tested on OS X, Linux, and Windows across Python versions 3.9 to 3.12 and has no runtime dependencies beyond the compiled extension itself.

Use it when JSON parsing speed matters in your application—for example, processing large JSON documents or handling high-throughput data pipelines where parsing becomes a measurable bottleneck. For typical applications where JSON parsing is not performance-critical, the standard library is simpler and equally sufficient.

Use it for:

- Parse large JSON files or streams where speed is a bottleneck in data processing pipelines.
- High-throughput API servers that deserialize incoming JSON requests and need to minimize parsing latency.
- Data science workflows that load JSON-formatted datasets and benefit from faster deserialization.
- Real-time analytics systems that ingest JSON events and require low-latency parsing.
- Batch processing jobs that read many JSON records and need to reduce overall wall-clock time.

## Worth the install?

AI-flagged interpretation of the facts above — verify before relying.

Python bindings for the simdjson SIMD-accelerated JSON parser, with automatic fallback to a standard parser when SIMD instructions are unavailable.

Yes, if JSON parsing speed is a measurable bottleneck in your workload. The package is stable, has no known vulnerabilities, and works across common platforms. However, verify the license terms first (they are not declared in the metadata), and note that maintenance is aging—last release was 412 days ago. For typical applications, the standard library is simpler and equally sufficient.

## Install

pip install pysimdjson
uv add pysimdjson
poetry add pysimdjson

## Installing pysimdjson

Before you install: Medium install friction due to compiled wheels for multiple platforms and Python versions (3.9–3.12). Last release was 412 days ago; maintenance status is aging, so expect slower response to issues or updates.

License in practice: License treatment is unclear—no SPDX identifier or raw license text is available in the metadata. Verify the actual license before using in proprietary or copyleft-sensitive projects.

Quickstart:

pip install pysimdjson

import pysimdjson
parser = pysimdjson.Parser()
result = parser.parse(b'{"key": "value"}')
print(result)

Requires Python 3.9 or later. Installation requires a compatible wheel or source build for your platform.

Verify before relying:

- Actual license identifier and terms—metadata lists neither SPDX nor raw license text.
- Current maintenance status and responsiveness—last release was 412 days ago; repo metadata unavailable.
- Performance gains relative to the standard library json module in typical workloads.
- Whether the fallback parser on non-SIMD platforms matches the speed of alternatives.
- Exact API surface and usage patterns beyond basic parsing.

## Package facts

- License: not declared (unclear)
- Python support: supports_current
- Install friction: medium
- Maintenance: aging
- Downloads: 1.5M/month (top 5,000 on PyPI)
- Known vulnerabilities: none known

## Tags

fast json parsing, simd json parser, high performance json, json parsing library, accelerated json decoder, json performance, python json bindings, json-parsing, simd-acceleration, performance

[View on SkillFed](https://skillfed.io/packages/pysimdjson) · [View on PyPI](https://pypi.org/project/pysimdjson/)