Is your video the right length to go viral?
Pick a platform and enter your duration. Get an algorithm-aware verdict on whether you're in the sweet spot — or missing it by seconds.
YOUTUBE SHORTS · TIKTOK · INSTAGRAM REELS · LONG-FORM
In the sweet spot for YouTube Shorts
- 30s sits inside the 25s-55s range the algorithm prefers.
- Focus your effort on the first 3 seconds — that's what decides completion rate.
YOUTUBE SHORTS RULES
Shorts max out at 3 minutes, but the Shorts shelf strongly favours 25-55s. Anything under 15s struggles with hook-delivery time; anything over 90s rarely retains audience.
MIN
1s
SWEET SPOT
25s–55s
MAX
3m
WHY LENGTH MATTERS
Each platform has its own bias.
Four platform rulesets
Distinct sweet-spot ranges for YouTube Shorts, TikTok, Instagram Reels, and long-form YouTube — each with its own algorithm bias.
Sweet-spot verdict
Get a green / amber / red read on whether your duration sits inside the range the platform actively rewards.
Retention-aware notes
Every verdict comes with guidance on what the number means for completion rate and shelf placement.
LENGTH IS ONE SIGNAL. YOUR AUDIENCE IS THE REST.
Duration is a rule of thumb.
Retention OS is the real map.
VANTAGEVID analyses actual second-by-second retention on your channel, finds the pacing patterns in your outliers, and predicts where your next video will drop viewers — long before you hit publish.
JOIN THE WAITLIST · FREE · NO CREDIT CARD
Frequently asked
Is there an ideal length for YouTube Shorts?
The Shorts shelf strongly favours 25-55 seconds. Under 15s struggles with hook-delivery time; over 90s rarely retains audience even though the platform allows up to 3 minutes.
What's the sweet spot for TikTok?
For most niches, 21-34 seconds delivers the highest completion rate on the FYP. Longer videos work — but only if the first 3 seconds pay off.
How short can Instagram Reels be?
Reels allow up to 90 seconds, but completion-rate analytics show 7-15s outperforms. Shorter loops get re-watched, which counts as additional views.
Does this matter for long-form YouTube?
Yes — the 8-12 minute range unlocks mid-roll ads and sits inside the "watch session" window the algorithm favours. Under 4 minutes loses ad-tier.
Does this replace real retention analysis?
No — length is just one signal. Retention OS inside VANTAGEVID maps second-by-second audience drop-off against your hook, pacing, and mid-video beats. That's the full picture.