---
id: fit-tool
version: "0.9.16"
license: BSD-3-Clause
license_treatment: permissive
maintenance: active
---

# fit-tool — A library for reading and writing Garmin FIT files.

License: permissive · Maintenance: active · Downloads: 145.5K/mo

## What it is and what it does

fit-tool is a Python library for reading, writing, and validating Garmin FIT files—the binary format used by Garmin devices to store fitness activities, workouts, and courses. It provides both a high-level API (FitFile for loading and serializing, FitFileBuilder for construction) and a CLI for quick conversions to CSV. The library includes composable validation at multiple conformance levels and supports both PRESERVE and CANONICAL encoding modes.

The package is a community-maintained fork after the original was removed from PyPI. It bundles FIT Profile version 21.212.0 and supports Python 3.9 through 3.14. Runtime has no third-party dependencies, making installation and deployment straightforward. The documentation explicitly defines capability boundaries and validation levels, so you know what is and isn't supported before relying on it.

Use it for:

- Convert Garmin activity files to CSV for analysis or import into other systems
- Stream large FIT files with bounded memory for processing without loading entire file
- Build and export custom Activity or Workout FIT files programmatically
- Validate FIT file integrity and conformance to Garmin specifications
- Parse GPS and fitness metrics from Garmin device exports for data pipeline integration

## Worth the install?

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

Reads and writes Garmin FIT files for Activity, Workout, and Course workflows, with support for parsing, validation, streaming, and format conversion.

Yes. Low install friction, no dependencies, active maintenance, permissive license, and no known vulnerabilities make it a safe choice. The explicit capability boundary documentation and multiple validation levels show mature design. Suitable for production use in fitness data pipelines, though real-world validation against Garmin devices should be verified for your specific workflow.

## Install

pip install fit-tool
uv add fit-tool
poetry add fit-tool

## Installing fit-tool

Before you install: Low friction: pure Python with no runtime dependencies. Active maintenance with a release 9 days ago. Community-maintained fork after original author removal.

License in practice: BSD-3-Clause permissive license allows commercial and private use with minimal restrictions.

Quickstart:

pip install fit-tool

from fit_tool import FitFile

fit = FitFile.from_file("activity.fit")
fit.to_csv("activity.csv")

Verify before relying:

- Extent of Activity/Workout/Course workflow support beyond basic read/write
- Real-world validation accuracy against Garmin devices and official tools
- Performance characteristics for large or complex FIT files

## Package facts

- License: BSD-3-Clause (permissive)
- Python support: supports_current
- Install friction: low
- Maintenance: active
- Downloads: 145.5K/month (top 15,000 on PyPI)
- Known vulnerabilities: none known

## Tags

garmin fit file parser, read write fit files, activity data garmin, fit file converter, garmin activity reader, fit format library, cycling gps data, garmin-fitness, binary-format, data-conversion

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