Markdown headings that make notes searchable
Use one # heading as the note’s title, then ## for sections and ### for sub-sections, without skipping a level. Apps build outlines and tables of contents from those headings, and Obsidian can search inside a single section, so clear headings make a note easier to search and to scan.
Why headings change how you find things
A heading is more than large text: it marks where a section starts and ends. Notion’s table of contents block lists the headings on a page, and Notion’s help page says indented headings are left out of it. Obsidian’s search has a section: operator that finds words in the same section. That is why real headings, not bold text, decide how searchable a note is.
Headings are also link targets. Obsidian’s help page shows a link such as [[About Obsidian#Links are first-class citizens]] that jumps straight to a section. None of this works on a bold line or a big font, only on real headings.
A converted PDF often arrives with headings at odd levels, or with section names that are only bold text. Fixing that takes minutes and pays back every time you search, link or skim.
Tidy a note’s headings in six steps
- List the headingsScroll through the note, or open its outline or table of contents, and write down each heading with its level. A converted PDF usually shows its problems here within a minute.
- Keep one H1The first # heading names the note. If several top-level headings exist, keep the first as the title and demote the rest to ##. Two titles in one note read as two notes.
- Close the gapsSections sit under the title as ##, and their parts as ###. If the levels jump from ## to ####, move the #### headings up one level.
- Stop at the depth your app handlesNotion offers three levels, so use #, ## and ### there, as Import Markdown into Notion explains. Obsidian takes six, but most notes need no more than four.
- Rewrite vague headingsSwap “Introduction”, “Notes” or “Page 3” for the phrase you would type into the search box, such as “Active transport across membranes”. For study notes a question also works: “How does a cell take in glucose?”
- Test with a searchSearch for a phrase from the middle of the note. In Notion add a table of contents and check that every section shows. In Obsidian try the section: operator. Fix anything that does not show.
Gaps closed, depth capped
On the left, headings as a messy PDF might give them. On the right, what the converter writes for Notion.
# Biology 201 notes
## Cells
#### Membranes
##### Transport proteins
#### Organelles
## Energy
#### Glycolysis# Biology 201 notes
## Cells
### Membranes
### Transport proteins
### Organelles
## Energy
### GlycolysisThe converter keeps the first heading as the title, renumbers the others in order with no gaps, and stops at three levels for Notion, Evernote and Apple Notes. Obsidian, OneNote and Logseq formats keep up to six.
How each app uses headings
The first column names the app, the second what headings do there, and the third how deep the ocrtomarkdown format goes.
| App | What headings do there | Levels in our format |
|---|---|---|
| Notion | The table of contents block lists them, except indented ones. Three heading levels exist. | Three |
| Obsidian | Search with section:, link to a heading with [[Note#Heading]], and read the Outline pane. | Six |
| Evernote | Pasted # lines convert to headings. | Three |
| OneNote | Copy formatted pastes headings as formatting. Check how OneNote styles them. | Six |
| Apple Notes | Imports Markdown on macOS, iOS and iPadOS 26 and later. Apple does not say which elements convert, so check the headings. | Three |
| Logseq | Every heading is a bullet in the outline. | Six |
Headings are the same Markdown everywhere. What differs is what each app builds from them.
What goes wrong with headings
Most heading problems come in these six shapes.
Bold lines pose as headings
A bold line is only styled text, so outlines, tables of contents and section search skip it. Chapter and section names in bold are a common case. Put # in front of the name instead.
Two top-level headings
A second # makes one note look like two. Keep one title and use ## for everything else. The converter turns a later # into ## without disturbing the ## headings already there, so check the outline for two sections that should have been one.
Skipped levels
Jumping from ## to #### leaves an empty rung in the outline and confuses anyone skimming it, including you in a year.
Twelve sections called Notes
Search finds all twelve and tells you nothing. Name each section for what is in it.
Too deep for the app
Notion has three levels, and the Notion format writes anything deeper as a third-level heading, so a fifth-level heading lands beside its parent instead of beneath it. Check the outline after converting.
Page furniture as headings
A running header can be read as a heading. Lines that repeat three or more times are removed, but glance through for stragglers. Slide decks are the usual source: Lecture slides to study notes covers them.
How ocrtomarkdown helps
ocrtomarkdown keeps the first heading as the single title, renumbers the rest in order without gaps, and caps the depth for the app you pick. It leaves a bold line as bold text and does not invent headings the PDF never had, so adding a ## where a section starts is your pass. Convert on the converter page and read the Preview tab. Free: 3 files a day, up to 10 pages each, no account. Files over 10 pages are converted up to page 10 on the free allowance; a page code converts the whole file, up to 150 pages. See pricing.
Headings in Markdown notes: your questions
How many H1 headings should a note have?
One. It is the note’s title, and everything else sits beneath it as ## and ###.
What is the difference between # and ##?
The number of # signs is the level. One is the title, two is a section, three is a part of a section.
How many heading levels does Notion have?
Three, according to Notion’s help page. Toggle headings are the same three sizes made collapsible.
Can I search by heading in Obsidian?
Its search has a section: operator that finds matches in the same section, which is the text between two headings.
Why is a heading missing from my table of contents?
Notion’s help page says indented headings are not included. Move the heading out to the top level of the page.
Does the converter add headings to a PDF that has none?
No. It keeps and orders the headings it finds. Add a ## yourself where each section begins, then check the outline.
What happens to a bold line?
It stays bold text. Only lines read as headings become # lines, so promote a bold line by hand if it is one.
Should headings be short?
A short, specific phrase works best, because it is what you see in an outline and in search results.