Presentation Font Size Calculator — How Big Must Text Be?
Enter how far the farthest person sits and how big the screen is, and get the minimum font size in points that stays readable from the back row — plus a stricter size for numbers and detail. Based on the legibility rule AV designers use to size screens.
Room & screen
Minimum font size
| Distance (ft) | Body text | Numbers & detail |
|---|---|---|
| 10 | 10 pt | 14 pt |
| 15 | 16 pt | 20 pt |
| 20 | 20 pt | 26 pt |
| 30 | 30 pt | 38 pt |
| 40 | 38 pt | 52 pt |
| 60 | 58 pt | 76 pt |
How it works
- Legibility rule: comfortable reading needs text roughly 1/200 of the viewing distance in height (1/150 for detail like table numbers). At 30 ft that is 1.8 inches of cap height on the screen.
- Cap height is about 0.7 of the font size, so the physical font height on screen must be cap height ÷ 0.7.
- The screen shows your slide scaled up: scale = screen width ÷ slide width. Divide the required on-screen height by that scale to get the height on the slide, and multiply by 72 to get points.
- Screen width comes from the diagonal and aspect ratio you enter — a 100-inch 16:9 screen is 87 inches wide.
- Results round up to the nearest even point size. Headings should be about 1.5× body text.
Frequently asked questions
What is the minimum font size for a presentation?+
For a typical meeting room (viewers within 20–30 ft of a 80–100 inch screen) about 24–28 pt body text and 36+ pt headings. Small rooms with a large TV can go down to 18–20 pt; auditoriums need 32 pt or more.
Is 12 pt too small for slides?+
Almost always. 12 pt on a standard slide is unreadable beyond a few metres. If you must show fine print, put it in a handout, not on the screen.
Why does slide size matter?+
Because a point is 1/72 of an inch on the slide, not on the screen. A 24 pt font on a 10-inch-wide Google Slides slide is projected larger than 24 pt on a 13.333-inch PowerPoint slide shown on the same screen.
Where does the 1/200 rule come from?+
It is the common AV-industry guideline (related to the InfoComm/AVIXA DISCAS standard) for sizing displays so that text remains legible; 1/150 is the stricter figure for analytical viewing such as spreadsheets.