Coming from Calendar

The Calendar plugin draws one month grid and marks days with dots. Everything it does has an equivalent here, usually a more configurable one.

In Calendar	In Journals
Dots sized by word count	Decorations with note-size conditions — see Word-count dots below
A hollow dot for incomplete tasks	A decoration with Check if note has open tasks or Check if all tasks are completed
Colouring days by tag or content	Decoration conditions on title, tag, frontmatter property, note size or weekday, painting colors, borders, shapes, corners and icons
One calendar per vault	Any number of journals, grouped on shelves, with views scoped to a shelf
A fixed month grid padded to six weeks	A month grid of exactly the weeks the month spans, plus week grids, notes-by-date lists and toolbars composed into a view
Week numbers on the left	Before weekdays, After weekdays or Hidden, globally or per calendar block
Clicking a day or week number	Clicking any period — day, week, month, quarter or year — from its cell or heading
Reveal active note command	Follow active note on a view, which moves the view as you open notes
Start of week from the locale, or a locale override to change it	Week configuration, which sets the first day of the week and week 1 of the year, independently of your Obsidian language
Notes found by file name in one folder	Notes identified by their properties, so they keep working when moved or renamed — see Your existing notes

Two things Calendar has no equivalent for: a note's creation date for Notes by date can come from a property rather than the file, and a day can hold any number of extra notes through notelets.

Your existing notes

The import reads Calendar's week start and its weekly note when it shows one, and core Daily notes' setup for the daily notes Calendar displays; it sets up the matching journals and connects the notes you already have. The steps below cover only the daily journal, by hand.

Calendar shows the daily notes that the core Daily notes plugin — or Periodic Notes, when it is on — creates, and finds them by file name. Journals finds notes by their properties instead, and adopts a note that was already in your vault only when you rename or move it onto a path the journal would use — so a new journal starts with an empty calendar. For your daily notes:

1. Create a daily journal whose Folder is the folder your daily notes are in. Its Note name template {{date}} and Default date format YYYY-MM-DD match Daily notes' own default; if you changed that format, use yours. New notes then land beside the old ones.
2. Connect the old notes with Bulk add: Source folder that folder, Read the date from Note title, and the same date format. The first run is a dry run, which only lists what it would do.

If Periodic Notes was doing the filing behind Calendar and its format put part of the date in folders, pick Note path instead of Note title — it reads the whole folder-and-name layout back, where Note title alone cannot tell which folder a note came from.

Weekly notes go the same way, into a weekly journal. Calendar names them with its Weekly note format, which it offers while Show week number is on and Periodic Notes' weekly notes are off.

Word-count dots

Calendar draws one dot per 250 words, up to five. In Journals that is five decorations on the daily journal, each drawing one dot in the same position, so they stack:

Decoration	Condition	Style
1	Check if note exists	a small circle
2	Check note size — Words > 500	a small circle
3	Check note size — Words > 750	a small circle
4	Check note size — Words > 1000	a small circle
5	Check note size — Words > 1250	a small circle

A note of 800 words matches the first three and shows three dots. A note of 1300 words matches all five, but Marks shown per position caps how many are drawn: at its default of 3 it shows two dots and +3. Set it to Unlimited, or to at least 5, to see all five. The run behind these numbers is under Word-count bands.

For one dot per band instead of a growing row, put two note-size conditions in one decoration — >= 250 and < 1000 — so it matches only inside that band, and give each band its own color.