---
title: OWLF
description: Open Wellbeing Log Format. One open file for mood and wellbeing data, readable by any app.
sidebar:
  label: Introduction
---

**OWLF is an open, app-neutral file format for mood tracking data.** One `.owlf.json` file holds one person's entries from one app: mood, sleep, emotions, tags, people, notes and journal prompts.

Version 0.1 comes with adapters for 21 apps and exporters to CSV, Excel and PDF. Everything runs in the browser and in React Native. Nothing is uploaded.

```txt
Daylio export ──adapter──▶ data.owlf.json ──▶ CSV · Excel · PDF · Pixy
```

## Why OWLF?

Every mood app exports its own shape: a ZIP of JSON, a CSV with app-specific columns, a PDF. Moving to another app means one converter per pair of apps. OWLF is the shared middle: read an export once, write any target.

- **Keeps source values.** The app's own scale, labels and emotion names stay in the file. Each consumer maps them its own way and can explain every choice.
- **Local day first.** Every entry belongs to the calendar day the person saw in the app, never a day derived from UTC.
- **Counts what is lost.** Fields the format cannot hold are counted per entry, never dropped silently.
- **No app is special.** Nothing in the format belongs to one app.

**[Document](/format/document)**

The top-level `.owlf.json` object and its fields.

**[Supported apps](/adapter-authors/supported-apps)**

21 apps with an adapter package on npm.

**[Read and write OWLF](/app-developers)**

Validate files, export CSV, Excel or PDF, import into Pixy.

**[Build an adapter](/adapter-authors)**

Add an app: synthetic fixture, conformance check, npm package.