Flask-JSON
Better JSON support for Flask
Decision gist · record as of 2026-08-14
Yes, if you are working with an existing Flask codebase already using Flask-JSON or need its specific convenience features—the code is stable and has no known vulnerabilities. No, if starting a new project: the package is abandoned and unsupported, and modern Flask has improved its own JSON handling, making this extension less necessary. Evaluate whether Flask's native support or a maintained alternative better fits your needs.AI-flagged interpretation of the facts on this page — verify before relying
Before you install
- Installation is straightforward with low friction—a single dependency on Flask.
- However, the package is abandoned; the last commit was 2023-08-09 and no releases have occurred since 2023-05-06, so maintenance and security updates are not forthcoming.
License · maintenance · safety
BSD (permissive) — BSD license is permissive, allowing use in most commercial and open-source projects with minimal restrictions.
last release 2023-05-06 (1196 days) · last repo commit 2023-08-09 · 45 stars
0 known vulnerabilities (OSV.dev, 2026-08-14) · 82,620 downloads/mo, #14,152 on PyPI
Alternatives
Verify before relying
from flask import Flask
from flask_json import FlaskJSON, json_response
app = Flask(__name__)
FlaskJSON(app)
@app.route('/data')
def get_data():
return json_response(status='ok')- Whether the package works reliably with current Flask versions beyond 2023-05-06
- Whether datetime and other extended type serialization remains compatible with modern Python JSON standards
What it is and what it does
Flask-JSON is a lightweight extension that wraps Flask's native JSON handling to provide more convenient response generation and error handling. It introduces decorators like `@as_json` and functions like `json_response()` that simplify returning JSON from routes, and adds a `JsonError` exception for structured error responses. It also extends JSON encoding to handle types like datetime objects that Flask's default encoder does not support.
The package depends only on Flask and installs with no additional system requirements. However, it has been abandoned since mid-2023 with no active maintenance, meaning bugs and compatibility issues with newer Flask or Python versions will not be addressed by the maintainer.
Use it for
- Simplify JSON endpoint responses in Flask apps by using json_response() instead of manual response construction.
- Return structured error responses with custom codes and descriptions using JsonError exceptions.
- Serialize datetime and other non-standard types directly in JSON responses without custom encoders.
Worth the install?
AI-flagged interpretation of the facts on this page. Verify before relying on it.
Yes, if you are working with an existing Flask codebase already using Flask-JSON or need its specific convenience features—the code is stable and has no known vulnerabilities.
No, if starting a new project: the package is abandoned and unsupported, and modern Flask has improved its own JSON handling, making this extension less necessary. Evaluate whether Flask's native support or a maintained alternative better fits your needs.
Install
flask-json on PyPI
Before you install
Installation is straightforward with low friction—a single dependency on Flask. However, the package is abandoned; the last commit was 2023-08-09 and no releases have occurred since 2023-05-06, so maintenance and security updates are not forthcoming.
License in practice
BSD license is permissive, allowing use in most commercial and open-source projects with minimal restrictions.
Quickstart
from flask import Flask
from flask_json import FlaskJSON, json_response
app = Flask(__name__)
FlaskJSON(app)
@app.route('/data')
def get_data():
return json_response(status='ok')Verify before relying
- Whether the package works reliably with current Flask versions beyond 2023-05-06
- Whether datetime and other extended type serialization remains compatible with modern Python JSON standards
Package facts
| License | BSD permissive |
| Python support | Not specified |
| Install friction | Low. Pure-Python wheel |
| Runtime dependencies | 1 packageFlask |
| Maintenance | Abandoned 1,196 days since the last release |
| Last repo commit | |
| First released | |
| Downloads | 82,620 / month, #14,152 on PyPI 30-day window, as of 2026-08-14 |
| Known vulnerabilities | None known OSV.dev, checked 2026-08-14 |
| Classifiers | Development Status :: 4 - BetaEnvironment :: Web EnvironmentFramework :: FlaskIntended Audience :: DevelopersLicense :: OSI Approved :: BSD LicenseOperating System :: OS IndependentProgramming Language :: PythonProgramming Language :: Python :: 3Topic :: Internet :: WWW/HTTP :: Dynamic ContentTopic :: Software Development :: Libraries :: Python Modules |
Evidence: Flask_JSON-0.4.0-py3-none-any.whl
Tags
Let your AI agent find packages like this
Example. Real query, live index.
You found this page by searching. An agent finds it by wishing: SkillFed indexes 14,416 PyPI packages by what they can do, searchable in plain language.
wish › “flask json response helper”
- Flask-JSONFlask-JSON adds convenient JSON response generation and error…
- flask-orjsonReplaces Flask's default JSON encoder with orjson, a faster JSON…
- flask-marshmallowFlask-Marshmallow integrates Flask and marshmallow to…
Give your agent the search over MCP, or paste the wish link into any chat.
More Python Modules packages
Converts domain names between Unicode and ASCII-compatible encoding (Punycode) according to IDNA 2008 and Unicode Technical Standard 46, with security validation and broader script coverage than the standard library.
Install it if you work with internationalized domain names, need to validate domains, or use HTTP clients that depend on it transitively.
Setuptools is a Python build backend and package management tool that handles building, distributing, and installing Python packages, including support for C/C++ extension modules.
PyYAML parses and emits YAML 1.1 data format, enabling serialization and deserialization of configuration files and Python objects to and from human-readable YAML text.
Pydantic validates Python data structures against type hints, coercing and checking input at runtime to ensure it matches a declared schema.
Provides reusable metadata objects for use with PEP-593 `typing.Annotated` to express common constraints like bounds, collection sizes, and predicates on types.
Install it if you use or build libraries that need to express type constraints in a standardized, inspectable way—or if you want to annotate your own types with…
Provides runtime tools to inspect and introspect Python type annotations, enabling programmatic examination of type hints at execution time.
See also flask-marshmallow · flask-cors · flask-orjson · Flask-HTTPAuth · Flask-Session · Flask-Mail · Flask-Login · Flask-Moment · Flask-Threads · nsj-rest-lib2