Char Limits
Cross-post one draft, see at a glance which platform it fits: title length, total length, longest line.
Try it now
Paste one draft. The six platform cards update live — green = ok, yellow = close, red = over.
- X / Twitter— / 280
Free tier caps at 280; Premium reaches 25k. Links and media don't count.
- Xiaohongshu— / 20— / 20 longest line
Title ≤ 20; keep each line ≤ 20 chars — over won't error but breaks the visual flow.
- Douyin— / 55— / 2200 total
Title ≤ 55 chars; caption ≤ 2200.
- TikTok— / 2200
Caption ≤ 2200 chars; hashtags in #Topic format.
- YouTube— / 100— / 5000 total
Title ≤ 100 (front-end shows ~70); description ≤ 5000; tags ≤ 500.
- WeChat OA— / 64
Title ≤ 64; body has no hard cap but 1000–3000 chars finishes best.
How the check works
- The primary metric per platform: 小红书 / 抖音 / YouTube / WeChat OA watch the title (first non-empty line); X and TikTok watch total length.
- 小红书 also checks the longest line — the platform wraps at ~20 chars in practice, longer lines look broken.
- Green = ≥ 30% room left; yellow = 70–100% used; red = over.
- "Title" = first non-empty line of the first non-empty paragraph, after stripping leading markdown markers.
- All counts use Unicode code points — one emoji or one CJK char = 1, no surrogate-pair double-count.
Use cases
The most common cross-post workflow: same article to 小红书, 抖音, X, YouTube Shorts. Each platform caps things differently, titles rarely survive the round-trip unchanged. Paste once and the six cards light up where you need to trim or restructure.