WeChat Specifications

Moments Photo

Dimensions	1080 × 1080 px recommended
Max File Size	5 MB per image
File Formats	JPG, PNG
Notes	Up to 9 photos per Moments post; square format displays best

Official Account Article Cover

Dimensions	900 × 383 px (2.35:1, main headline) or 200 × 200 px (secondary/multi-article list)
Max File Size	5 MB
File Formats	JPG, PNG, GIF
Notes	Main headline image uses a 2.35:1 ratio (updated from the older 900×500 / 16:9 layout); secondary articles in a push: 200×200

Profile Photo

Dimensions	No fixed pixel requirement; 300 × 300 px recommended (square)
Max File Size	2 MB
File Formats	JPG, PNG, GIF, BMP
Notes	Displayed as a circle; WeChat auto-crops/compresses on upload

Official Account Avatar

Dimensions	300 × 300 px recommended
Max File Size	2 MB
File Formats	JPG, PNG, GIF, BMP
Notes	Square format; displayed at small sizes in feeds

Moments Video

Max File Size	100 MB
File Formats	MP4, MOV
Resolution	1080 × 1920 px (vertical) or 1920 × 1080 px (horizontal)
Max Duration	Up to 5 minutes
Notes	H.264 recommended; videos autoplay silently in feed; duration expanded from 30 seconds in March 2025

Video Channel (Shipinhao) Post

Max File Size	2 GB
File Formats	MP4, MOV
Resolution	1080 × 1920 px (vertical, 9:16 preferred); 1080p+ recommended
Max Duration	Up to 60 minutes on mobile (up to 8 hours via the desktop uploader)
Notes	WeChat's short-video platform; H.264 recommended. Limits were raised in stages (30 min, then 1 hour / 2 GB) since launch — mobile app enforces the 60-minute/2GB cap most users see

Official Account Article Video

Max File Size	20 MB for direct upload to the article media library
File Formats	MP4
Max Duration	Up to 30 minutes
Notes	Embedded inline in WeChat official account articles; videos over 20 MB must be hosted on Tencent Video and embedded by link instead of direct upload

Moments Text Post

Character Limit	1,500 characters

Official Account Article

Character Limit	No official hard limit characters per article (recommended 3,000–6,000 for readability)
Notes	Rich HTML article; supports images, video, audio embeds. WeChat does not publish a strict character cap for image-text articles — length is practically unlimited, though very long articles are discouraged for reader engagement

Nickname

Character Limit	20 characters

Bio

Character Limit	30 Chinese characters (up to ~60 for Latin characters)
Notes	Refers to WeChat's personal signature (个性签名) field

Chat Message

Character Limit

5,000 characters

Notes

WeChat's official Help Center (cs.help.wechat.com, 'How Do I Use Broadcast Messages?', checked Aug 2026) states a hard cap of 'up to 5000 characters per message' for Broadcast Messages — the feature that sends one message to up to 200 individual contacts through the same single-message compose flow as a regular 1:1 chat message. WeChat still does not publish a limit specifically labeled for ordinary 1:1/group chat, but since Broadcast uses the identical message-send pipeline, 5,000 is now backed by an official source rather than a pure estimate. Older user reports of ~650 characters likely reflect legacy client versions or a UI wrap/warning threshold rather than a hard send limit

Profile Photo

Dimensions	No fixed pixel requirement; 300 × 300 px recommended (square)
Max File Size	2 MB
File Formats	JPG, PNG, GIF, BMP
Notes	Displayed as a circle; WeChat auto-crops/compresses on upload

Official Account Cover

Dimensions	900 × 383 px (2.35:1)
Max File Size	5 MB
File Formats	JPG, PNG, GIF
Notes	Shown on the Official Account profile page; updated from the older 900×500 / 16:9 ratio

Moments Ad (Image)

Dimensions	800 × 800 px (1:1, standard); other ratios (640×800, 800×640, 1280×720) supported for select card/carousel formats
Max File Size	≤ 1 MB recommended (oversized files are auto-compressed; some formats allow up to ~1.7 MB)
File Formats	JPG, PNG
Notes	Appears in Moments feed; multi-image carousel supports 3/6/9 images. Sources disagree on the exact file-size ceiling (300 KB–1.7 MB) depending on ad format — confirm current limits in Tencent Ads Manager before a campaign

Moments Ad (Video)

Max File Size	100 MB (horizontal); vertical formats may cap lower (~30 MB)
File Formats	MP4
Resolution	1280 × 720 px or 1280 × 960 px (horizontal); 720 × 1280 px (vertical)
Max Duration	6 – 15 seconds (some vertical/full-screen formats allow up to 30 seconds)
Notes	Autoplays silently in Moments; exact duration/size caps vary by ad format (standard, card, full-screen) — confirm in Tencent Ads Manager

Bottom-of-Article Ad (底部广告位, 流量主/Media Partner)

Dimensions	System-determined — no fixed advertiser-facing creative spec
Max File Size	Not applicable
Notes	Confirmed real placement, but NOT a fixed-spec advertiser product: this is the 流量主 (Media Partner/'Traffic Master') 底部广告位 ('bottom ad slot'), which sits between the article body and the comment section. Per WeChat's own developer community documentation (developers.weixin.qq.com/community), the placement is described as: '底部广告位位于图文消息内容区底部...系统会根据微信广告素材的定向和阅读文章的用户画像，匹配当前状态下最适合展示给用户的广告，流量主无须额外操作' — i.e. the system programmatically matches and serves creative based on ad targeting and reader profile; the publisher (流量主) does not upload or size a fixed banner, and advertisers don't design to one fixed dimension either. The previous entry's '640×100px / 200KB' figure is REMOVED — it could not be traced to any current official Tencent Ads or WeChat source in this pass and appears to be either outdated, conflated with a generic web-banner IAB size, or fabricated. This is a distinct product from Moments Ads (image/video, listed above) and from Mini Program in-app Banner Ads (which are a separate programmatic unit for app screens, not Official Account articles).

Ad Headline

Character Limit	30 characters
Notes	Moments ad brand name / title. Card-style ad titles are shorter (~10 characters); some regular ad formats allow up to 40 characters / 4 lines of body copy