There are three Unicode styles that genuinely shrink letters, and people reaching for 'really tiny text' or a 'super tiny' bio usually want to know which one wins on size. Short answer: superscript renders smallest, subscript is a close second, and small caps is the largest of the three but the only one with a complete alphabet. Compare all three live on the tiny text generator.
This guide ranks them by rendered height, then explains the trade-off that matters more than raw size: letter coverage. A style that's tiny but drops half your capitals looks broken, not small.
Ranked by rendered size
Measured against a normal lowercase letter, superscript characters render at roughly 60–65% height, subscript at about 65–70%, and small caps at 75–80%. The gap between superscript and small caps is visible at a glance in a bio. Bold, cursive, and bubble are sometimes called 'tiny' but they only restyle letters — they're the same height as normal text.
The coverage trade-off
Superscript has a near-complete lowercase alphabet but is missing several capitals; subscript is the least complete, with only a partial lowercase set and almost no capitals. Small caps converts every letter. So the smallest style (superscript) is best for a short lowercase phrase, while a name or a line with capitals is safer in small caps even though it's a touch larger. See how to make tiny text for the step-by-step.
Readability at bio size
Social bios render at around 13–15px. At that size, superscript can get hard to read for anyone, and subscript worse. Small caps stays legible because the letterforms are simpler and evenly weighted. If the text needs to be read, not just noticed, small caps almost always wins.
Picking one
Want maximum shrink for a two or three word lowercase tagline: superscript. Want a whole bio line or anything with capitals and numbers to stay readable: small caps. Subscript is niche — reach for it only when you specifically want the below-the-line look.