TikTok slideshow myths: 18 common claims checked against sources

How were the verdicts decided?

Each claim gets one of three labels, based only on the sources linked next to it:

• Supported: an official page states it.
• Unsupported: no official page or reliable dataset states it. That does not make it false; it means you cannot rely on it.
• Contradicted: an official page states something different.

Everything is dated November 2026. Several Help Center pages were read in German and translated, which is noted where it matters. Platforms change their rules without notice, so check the linked page before you act on a limit.

What does the scorecard say at a glance?

Which claims do official pages contradict?

• "Instagram carousels hold 10 slides." The Help Center says up to 20 photos and videos, and the Graph API allows 20 container IDs (Meta for Developers (opens in a new tab)). Ten was the limit when Instagram announced carousels in 2017 (opens in a new tab). The rise to 20 was reported on 9 August 2024 by PetaPixel (opens in a new tab), a secondary source.
• "Instagram allows 30 hashtags." The Help Center now says five, and more than five on a photo or video means the comment will not post. Social Media Today reported on 18 December 2025 (opens in a new tab), quoting Instagram, that the limit would be updated gradually, so some accounts may still see more. The Graph API reference still says 30; its docs appear to lag.
• "TikTok's caption limit is 2,200 characters." The Creator Academy says up to 4,000, and the Content Posting API allows 4,000 for a photo description. The 2,200 figure comes from TikTok's October 2022 announcement (opens in a new tab). Some tools still show it; Hootsuite's change to 2,200 (opens in a new tab) was a limit of its own Create tool, not TikTok's.
• "TikTok photo posts stop at 10 photos." The Creator Academy and the API reference (opens in a new tab) both say 35. Third-party tools that list other numbers conflict with the official one. There is a related claim of a required minimum of two, three or four photos. No official page states a minimum, which is not proof that none exists, so test in the app before you publish a number.
• "Instagram caps feed photos at 4:5." The Help Center's supported range runs from 1.91:1 to 3:4, so 4:5 sits inside it. Instagram announced 3:4 support in May 2025, as PetaPixel reported (opens in a new tab).
• "Music works on carousels that include video." The Help Center says music can be added to a multi-photo post on mobile, not on computers, and not to carousels with videos. Third-party blogs that disagree are low confidence.

Which claims have no solid source behind them?

• "TikTok photo posts always beat video." Fanpage Karma (opens in a new tab) found carousels ahead on engagement rate; Buffer (opens in a new tab) found video ahead of images (3.39% versus 1.92%). Two vendor datasets pointing in opposite directions support neither side. The full comparison is in what makes slideshows perform.
• "TikTok says carousels get 2.9 times the comments and 1.9 times the likes." A marketing blog attributes this to TikTok. No TikTok source for it was found.
• "TikTok recommends 1080x1920." The Creator Academy only advises cropping all photos to the same ratio. Pixel sizes you see are community numbers. See TikTok slideshow size if you want the debate laid out.
• "Instagram ranking favors carousels." The official ranking post lists signals but no format preference. Carousel outperformance appears in vendor datasets, which is a different kind of evidence.
• "TikTok caps hashtags at five." Social Media Today reported in August 2025 that some users saw an in-app notice. TikTok made no statement.
• "Instagram shows a carousel a second time starting at slide two." One blog relays it as a comment by Instagram's head. No primary source was found, so do not build a plan around it.
• "You can officially mix portrait and landscape slides." PetaPixel reported it in October 2025; Instagram's Help Center says the chosen orientation applies to the whole post.
• "WCAG requires 4.5:1 contrast on TikTok or Instagram slides." WCAG covers web content and sets contrast ratios, not font sizes. Use 4.5:1 as a labeled benchmark for slide text, never as a platform rule.

One more claim often travels with these: "follower count decides TikTok reach." TikTok's 2020 Newsroom post says follower count is not a direct factor, though larger accounts naturally get more views, so neither extreme holds (TikTok Newsroom (opens in a new tab)).

Which claims hold up?

• Up to 35 photos in a TikTok photo post. Stated by the Creator Academy and the Content Posting API. Details in how many photos a slideshow can have.
• Music on TikTok photo posts. The Creator Academy says photo posts can have music, one sound per post.
• Photos and video in one Instagram carousel. The Help Center says they can be combined, and videos inside a carousel are not Reels.
• Alt text on TikTok photo posts. TikTok's Newsroom said on 23 May 2025 that creators can add it during upload or after publishing.

How can you check a new claim yourself?

1. Find who said it first. If the answer is "a blog", keep looking.
2. Look for the platform's own Help Center, Creator Academy or developer page.
3. If it is a statistic, ask for the dataset, the metric and the sample.
4. Check the date. Limits such as captions and hashtags have changed.
5. If only a tool's page says it, remember that a tool's limit is not the platform's limit.

The same test applies to claims about tools. For Fyslide, the FAQ states what it does today (it exports slides and a caption, and posting is marked "Coming soon") so you can check a claim against one page.

For caption specifics see TikTok slideshow captions, and for text that the interface can cover, the safe zone page. Ratio questions for Instagram are in the Instagram carousel size guide.