Day One to Obsidian Converter

Convert Day One journal exports to Obsidian-compatible Markdown files with full metadata preservation.

Browser Version

Looking for a client-side version that runs entirely in your browser?

• Try it online - No installation required
• JavaScript version repo - Pure JS implementation

This Ruby version offers a command-line tool and self-hosted web interface.

Features

• Reads Day One ZIP exports directly (or extracted directories)
• Supports all attachment types: photos, videos, audio, and PDFs
• Preserves all metadata in YAML frontmatter:
  • UUID, creation/modification dates, timezone
  • Tags (converted to Obsidian-friendly format)
  • Location (place name, city, region, country, coordinates)
  • Weather (conditions, temperature, humidity, wind, moon phase)
  • Activity (type, step count)
  • Device info (name, type, model, OS)
  • Photo metadata (camera, lens, date, dimensions)
  • Starred/pinned flags, editing time
• Converts dayone-moment:// image references to Obsidian ![[filename]] embeds
• Unescapes Day One's markdown escaping
• Handles duplicate filenames by appending UUID fragment
• Copies photos to attachments folder

Requirements

• Ruby 2.7+
• Bundler (gem install bundler)

Installation

bundle install

Usage

Web Interface (Recommended)

1. Start the server:

bundle exec ruby app.rb

2. Open http://localhost:4567 in your browser

3. Drag and drop your Day One export ZIP file

4. Download the converted Obsidian vault

Command Line

ruby dayone_to_obsidian.rb <input_path> <output_dir>

Arguments:

• input_path: Path to Day One export ZIP file or extracted directory
• output_dir: Directory where Obsidian vault will be created

Example:

ruby dayone_to_obsidian.rb ~/Downloads/Journal.zip ~/Documents/ObsidianVault/DayOne

Output Structure

output_dir/
├── entries/
│   ├── 2024-01-15 My Journal Entry.md
│   ├── 2024-01-16 Another Entry.md
│   └── ...
└── attachments/
    ├── abc123def456.jpeg
    └── ...

Frontmatter Example

---
uuid: 5E2B69750D5248378592CC8DAE174009
created: '2024-01-15T22:06:56Z'
modified: '2024-01-16T17:00:26Z'
timezone: America/Denver
starred: true
tags:
- travel
- food
location:
  name: Central Park
  locality: New York
  region: NY
  country: United States
  latitude: 40.782421
  longitude: -73.965606
weather:
  conditions: Clear
  temperature_c: 22
  humidity: 45
  moon_phase: Full Moon
activity:
  type: Walking
  steps: 8234
device:
  name: iPhone 15 Pro
  type: iPhone
  os: iOS
  os_version: '17.2'
photos:
- file: abc123def456.jpeg
  camera: Apple iPhone 15 Pro
  lens: iPhone 15 Pro back camera
  dimensions: 4032x3024
---

License

MIT