Chemical subscripts and exceptions

Lab notes are full of formulas like H2SO4 and NaHCO3. CommonNote recognizes them and displays the numbers as subscripts, so you see H₂SO₄. The text itself is unchanged, so search and copy still work with H2SO4. Words that only look like formulas, such as IC50 or HeLa, can be excluded.

Turn subscript display on or off

1. Open View options in the top bar.
2. Turn Chemical subscripts on or off. It is on by default.

When it is off, neither the subscript display nor the suggestion popup below appears.

Apply real subscript formatting

Subscript display only changes how the text looks on screen. If you want subscripts to survive export or pasting into another app, apply subscript formatting.

1. Type a formula. The suggestion appears only while the cursor is right after the formula — typing a space or punctuation closes it, so click before that. For a formula you already wrote, move the cursor right after it to bring the suggestion back.
2. A suggestion appears next to it, showing the molar mass in g/mol.
3. Click Subscript. The digits get subscript formatting, while the text is still H2SO4, so search is unaffected.

Exclude words that aren’t formulas

If a sample code or cell line is picked up as a formula, add it as an exception. There are three ways:

• Click Not a formula in the suggestion popup.
• Right-click a word shown with subscripts and choose the “…” is not a formula item.
• In View options, under Chemical subscripts, type the word in Never treat as formulas and click Add.

The exception list is saved to your account, so it applies on every device. It is case-sensitive: Hf50 and HF50 are different words. To take a word off the list, use the remove button next to it in the same place.

Words excluded from the start