# Platform signals — 2026 cheat-sheet

One citable home for the numbers that age fast. SKILL.md references this instead of scattering figures. Every line is dated (accessed **2026-06-02**) and sourced. Re-verify before relying on any of these past Q3 2026 — algorithm signals move quarterly.

## Distribution signals

| Signal | 2026 state | Source |
|---|---|---|
| Reels top distribution trigger | **Share-via-DM to a friend** carries the most weight for unconnected (non-follower) reach; shares/saves outrank likes; DM-sends moved from a secondary 2025 signal to the *primary* trigger | later.com "Instagram algorithm in 2026"; truefuturemedia.com Reels Reach 2026; mirra.my Instagram Algorithm 2026 |
| Retention | First **3 seconds** decide a Reel; watch-time/completion is the strongest retention signal — a fully-watched 15s beats a 60s most abandon | truefuturemedia.com; buffer.com Instagram Algorithm 2026 |
| TikTok completion bar | ~**70%+** completion to go viral (up from ~50% in 2024); **85%** completion trips a ~**4×** distribution multiplier | socialboostdigital.com; socialync.io TikTok Algorithm Changes 2026 |
| View velocity | Engagement inside roughly the **first ~30 minutes** of distribution is a dominant early signal | socialboostdigital.com; socialync.io |
| Discovery | Shifted from **hashtags to keywords** (caption/profile/on-screen text); hashtags no longer support follows; an **Originality Score** suppresses recycled/reposted content | truefuturemedia.com; creatorflow.so Instagram Algorithm 2026 |

## Length bands

| Goal | Band | Source |
|---|---|---|
| New-audience reach + completion | **7–30s** | socialpilot.co; syncstudio.ai Reels Algorithm 2026 |
| Depth with existing followers | **30–90s** | socialpilot.co; syncstudio.ai |
| Highest-viral band overall | **7–90s** | socialpilot.co; syncstudio.ai |

## Cadence and mix

| Item | 2026 figure | Source |
|---|---|---|
| TikTok consistency sweet spot | **3–5** quality posts/week | automateed.com; truescho.com; newzenler.com |
| Reels reach-vs-engagement optimum | **4–7** Reels/week | automateed.com; newzenler.com |
| Ceiling | **10+/week** → diminishing returns + burnout + dilution | automateed.com; truescho.com |
| Instagram weekly mix optimum | ~**3–4 Reels + 2–3 carousels + 1–2 statics** | thesecondbrain.io; reelbase.io; usevisuals.com |
| Carousel vs Reel engagement | Carousels ~**10%** avg vs ~**6%** for regular Reels; carousels get a 2–3× "second chance" impressions surge | thesecondbrain.io; usevisuals.com |
| Small-account caveat | **Reels remain the biggest visibility driver** for small accounts; lean Reels for growth, carousels for sales/community | reelbase.io; usevisuals.com |

## Trends, sounds, series

| Item | 2026 state | Source |
|---|---|---|
| Trending sounds | A **niche/category signal, not a raw boost** — a sound trending *within your niche* nudges TikTok to place your test cohort in that niche (raising completion); the 2022–2024 direct boost is gone. Adopt within **~24h** of trending | sproutsocial.com; opus.pro TikTok new algorithm 2026 |
| Series | Multi-part series drive ~**2.8×** higher return viewers; recurring formats build the habit the algorithm rewards | socialboostdigital.com; socialync.io |
| Trial Reels | Public IG accounts, **1,000+ followers**, since **July 2025** — publish to non-followers first to gather signal before showing existing audience; a built-in A/B surface for positioning/format bets | later.com; socialpilot.co |

## Positioning

| Item | 2026 state | Source |
|---|---|---|
| Niche lane | Specific lanes ("productivity for remote workers", "true crime in 5 minutes") grow; vague accounts do not. The algorithm rewards retention, so **faceless is viable if retention holds** | almcorp.com short-form mastery 2026; virvid.ai faceless 2026 |
