Make an Instagram carousel in Google Slides or PowerPoint

Both already sit on your machine, both let you set a square canvas, and both export images. That makes them a reasonable way to build a carousel without signing up for anything. The parts people get stuck on are the pixel size and the export, so start there.

Google Slides, step by step

  1. Open File → Page setup → Custom, switch the unit dropdown to Pixels, and enter 1080 by 1080. Use 1080 by 1350 if you want the taller portrait post.
  2. Design the first slide, then duplicate it for the rest so the margins and type sizes stay put.
  3. Paste your text slide by slide. Watch the bottom margin: nothing warns you when a line pushes past the safe area.
  4. Export with File → Download → PNG image. The menu says current slide, and it means it, so repeat for every slide. For the whole deck at once, download a PDF and convert its pages, or open the file in PowerPoint.

PowerPoint, step by step

  1. Open Design → Slide Size → Custom Slide Size. PowerPoint works in inches or centimetres, and it exports at 96 DPI by default, so 11.25 by 11.25 inches (28.58 cm) gives you a 1080 by 1080 pixel PNG. Portrait is 11.25 by 14.06 inches.
  2. Build the deck. Slide masters help here: put the background and the text frame on the master and every new slide inherits them.
  3. Export with File → Export → Change File Type → PNG, then choose All Slides. PowerPoint writes the set into one folder.
  4. If you need more than 96 DPI, Microsoft's documented route is a Windows registry value called ExportBitmapResolution. On a Mac that option does not exist, so size the slide for the pixels you want instead.

Where both start to hurt

The build is fine. The revision is the expensive part. A presentation deck has no idea that your slides are one continuous piece of writing, so adding a sentence to slide two leaves slides three through eight exactly as they were. You move the overflow along by hand and check every margin again. Do that weekly and it adds up.

Fonts are the other snag. A deck renders with the fonts installed on the machine that opens it, so a file moved between computers can reflow before you export.

The same job in a carousel tool

Cards was built for this one case. You paste the whole text once and it splits on word and line boundaries until each card is full, at the canvas size you picked. Change a paragraph and every slide after it re-splits and redraws. Export is a ZIP of the set, at 1× or 2×, with no watermark and no account for the first 8 cards.

Text goes in, the slides come out already laid out.
CardsSlides and PowerPoint
CostFree, Pro at $5 a monthFree with a Google account, or your Office licence
Building the slidesPaste the text once, the set comes outPlace the text on every slide by hand
Editing the text laterEvery slide re-splits and redrawsMove the overflow yourself, slide by slide
Canvas sizePresets for five social formatsSet once in page setup, applies to the whole deck
Exporting the setOne ZIP with every slideSlides: one PNG at a time. PowerPoint: all slides at once
Export resolution1× or 2× at the canvas sizeTied to slide dimensions and, in PowerPoint, to 96 DPI
Video of the deckMP4 with twelve motion presets, with ProSlide transitions, exported as a presentation video

Questions

What slide size should I use for an Instagram carousel?
1080×1080 pixels for square posts and 1080×1350 for portrait, which is the shape that takes the most feed space. Stories and Reels are 1080×1920. Set it once before you design, because changing it later rescales everything you have placed.
How do I set pixel dimensions in Google Slides?
File → Page setup → Custom, then switch the unit dropdown to Pixels and enter 1080 by 1080. The size applies to the whole presentation; Google Slides has no per-slide size.
Can Google Slides export all slides as images at once?
No. File → Download offers PNG and JPEG for the current slide only. To get the whole deck in one go, download it as a PDF and convert the pages to images, or open the file in PowerPoint and export from there.
How do I get exactly 1080×1080 out of PowerPoint?
PowerPoint measures slides in inches or centimetres and exports images at 96 DPI by default, so set the slide to 11.25 by 11.25 inches (28.58 cm) and the exported PNG lands on 1080×1080. Then File → Export → Change File Type → PNG, and choose All Slides. Higher resolutions need a Windows registry change to ExportBitmapResolution.
Is it worth using a dedicated carousel tool instead?
It depends on how often you post. For one carousel, a deck you already know is fine. If you publish weekly and revise your text, the manual rebalancing is the cost that repeats. Cards splits and lays out the text for you, exports the whole set as a ZIP, and is free for the first 8 cards without an account.