Exams are coming, and the folder for one module holds twenty lectures of forty slides each. Printed one slide to a page, that is eight hundred sheets for a single subject, and if the slides have dark backgrounds, the ink cartridge won’t last until lecture ten.
Everyone knows the answer is to put several slides on each sheet. The question every study group argues about is how many. Two wastes paper; nine might leave you squinting. This guide gives real numbers for how big a slide and its text come out at each choice, then covers saving ink and paper and getting the file to a print shop.
How small the text gets
Most lectures today are widescreen slides (16:9), 33.9 cm wide in PowerPoint. Printed on A4 with small margins, they come out like this:
| Slides per sheet | Best way round | Printed slide width | 24 pt text prints at about |
|---|---|---|---|
| 2 | upright | 19.3 cm | 13.7 pt |
| 3 | upright | 15.7 cm | 11.1 pt |
| 4 | sideways | 13.8 cm | 9.8 pt |
| 6 | upright | 9.4 cm | 6.7 pt |
| 9 | sideways | 9.1 cm | 6.4 pt |
| 3 with note lines | upright | 10.8 cm | 7.7 pt |
For comparison, textbook text is usually 10 to 12 pt. If your lecturer uses 24 pt for body text, which is typical, 4 slides per sheet keeps it close to textbook size, and that is what we suggest for most modules. 6 per sheet brings it down to about 7 pt: fine for headings and short bullet points, hard work for tables and equations.
The table hides a small surprise: with widescreen slides, 9 per sheet comes out almost the same size as 6, because the sheet turns sideways and fits three columns. If you were going to print 6, consider 9: nearly the same size, a third less paper.
Choosing by subject
- Detailed diagrams, equations or tables (anatomy, statistics, circuits): 2 or 3 per sheet. Small labels inside a chart are the first thing to disappear.
- Text with short bullet points (most theory lectures): 4 per sheet, the safe choice.
- Quick revision of a subject you know well: 6 or 9 per sheet. You need a reminder of each idea, not every line.
- A module you write on while studying: 3 with lines for notes beside each slide. The slides get a little smaller, and you get tidy space for your own explanations.
If you’re unsure, print one sheet first and try reading its smallest text at arm’s length.
Dark slides: the biggest ink drain
Navy or black slides with white text look good on screen, but on paper the printer has to cover almost the whole page to draw the background, leaving only the letters white. On our dark test slides, ink covered about two thirds of the page; turned into a white background with dark text, it dropped below a tenth.
The usual trick, “invert colours” in a viewer or printer setting, has an obvious problem: photos turn into negatives, red becomes cyan and green turns purple. So Print lecture slides lightens dark slides differently:
- The background becomes white and white text becomes black.
- Coloured text and charts keep their colour, darkened just enough to read on white paper, so a yellow title becomes a darker yellow.
- Photos stay exactly as they are.
- You see every changed slide before and after, and one tap switches any of them back to the original.
If you’re going to print in black and white anyway, choose “Black and white” or “Greyscale” in your printer’s own settings when you print. That works better than changing the file.
Halve the paper again: print on both sides
Once you’ve chosen how many slides go on a sheet, turn on double-sided printing, or ask the print shop for it. Four slides on each side means eight on every sheet of paper, so a 40-slide lecture needs 10 sides: just 5 sheets.
If you’re printing several lectures together, turn on Start each lecture on a new sheet. Then each lecture can be stapled on its own, and lecture three doesn’t begin on the back of lecture two.
Getting the file ready
- Collect your lectures as PDFs. If they are PowerPoint files, save them as PDF first: File › Save As › PDF on a computer, or Share and choose PDF on a phone. In Google Slides: File › Download › PDF document. If a lecture PDF asks for a password to open, unlock it first with Unlock PDF, using the password you were given.
- Open Print lecture slides and add the lectures in the order you want them.
- Choose how many slides go on each sheet. Each choice shows how many sheets you’ll need, and how many on both sides, so you can compare before deciding.
- If you like, leave out the title slides by typing their numbers under Leave out slides.
- Keep Turn dark slides light to save ink on, press Prepare for printing, check the slides that changed, and download the file.
The slides are laid out in the direction of their own language: English slides left to right, Arabic slides right to left, and you can change it. Everything happens in your browser, so your lectures are never uploaded.
Sending it to the print shop on WhatsApp
Plenty of students don’t have a printer at home and send the file to a print shop. A file with twenty lectures can be large for WhatsApp or slow to send. Turn on Make it smaller before preparing it, or shrink it afterwards with Compress PDF; pictures stay sharp enough to print. And tell the shop if you want both sides printed: that setting isn’t saved in the file.
Before you print the whole module
Print one sheet and check three things: the smallest text is readable, the dark slides came out light the way you want, and the order is right. It costs one sheet and saves reprinting a whole subject.
If all you need is two or four pages of an ordinary document on one sheet, a summary or a book chapter, Pages per sheet is simpler for that.