Reference · last reviewed
Character limits are not arbitrary numbers. They decide whether your hook survives the feed, whether an ad passes review, and whether a message is billed as one segment or three. Every limit CharLimits tracks is listed below, grouped by platform.
The main publishing field on each platform. Click any card to jump to its full table.
Social platforms set the tightest limits and change them most often. The numbers below cover the main publishing field on each network, plus the profile fields people get caught out by.
| Field | Limit | Notes |
|---|---|---|
| Post | 280 | X Premium accounts can publish posts up to 25,000 characters. |
| Display name | 50 | Shown above your handle. The handle itself is limited to 15 characters. |
| Bio | 160 | Profile links in the bio do not consume the 160 character budget. |
| Image alt text | 1,000 | Alt text is also read out by screen readers, so keep it descriptive. |
| Field | Limit | Notes |
|---|---|---|
| Caption | 2,200 | Only about 125 characters show before the More link in the feed. |
| Bio | 150 | Hashtags and mentions inside a bio count toward the same limit. |
| Username | 30 | Letters, numbers, periods and underscores only. No spaces. |
| Hashtags per post | 30 | Each hashtag itself may be up to 30 characters long. |
| Field | Limit | Notes |
|---|---|---|
| Caption | 2,200 | Newer app versions accept up to 4,000 characters on some accounts. Only about 100 characters show before the More link. |
| Bio | 80 | One of the shortest bio limits of any major platform. |
| Username | 24 | Must be between 2 and 24 characters. Underscores and periods allowed. |
| Comment | 150 | Comments are much shorter than captions. |
| Field | Limit | Notes |
|---|---|---|
| Post | 3,000 | Only about 210 characters show before the See more link. |
| Comment | 1,250 | Applies to comments on posts and articles. |
| Headline | 220 | Visible next to your name in search, feeds and comments. |
| About section | 2,600 | Only the first two or three lines show before See more. |
| Field | Limit | Notes |
|---|---|---|
| Post (technical max) | 63,206 | Practical best practice is under 125 characters for engagement. |
| Ad primary text | 125 | Anything longer is truncated in most placements. |
| Page name | 75 | Changing a page name is subject to review. |
| Comment | 8,000 | Comments on posts and reels share this limit. |
| Field | Limit | Notes |
|---|---|---|
| Post | 500 | Links and hashtags count toward the same 500 character budget. The feed collapses after roughly two lines. |
| Bio | 150 | Same limit as the connected Instagram account. |
| Username | 30 | Inherited from your Instagram handle. |
| Field | Limit | Notes |
|---|---|---|
| Post | 300 | Counted in grapheme clusters, not UTF-16 code units. |
| Display name | 64 | Also counted in grapheme clusters. |
| Bio / description | 256 | Newlines are supported and count toward the limit. |
| Field | Limit | Notes |
|---|---|---|
| Pin title | 100 | Only about 30 characters are visible in the grid view. |
| Pin description | 500 | The first 50 to 60 characters appear in search snippets. |
| Board title | 50 | Short board names are easier to scan and remember. |
| Profile bio | 160 | Keywords here help your profile surface in search. |
| Field | Limit | Notes |
|---|---|---|
| Post title | 300 | Most subreddit rules effectively require far shorter titles. |
| Text post body | 40,000 | Markdown formatting counts toward the total. |
| Comment | 10,000 | Applies to top level comments and replies. |
| Subreddit description | 500 | Shown in the sidebar and in search results. |
| Field | Limit | Notes |
|---|---|---|
| Message | 2,000 | Discord Nitro raises the limit to 4,000 characters. |
| About me | 190 | Shown on your user profile card. |
| Server name | 100 | Also used in invite links and search. |
| Embed description | 4,096 | Applies to webhook and bot embeds. |
| Field | Limit | Notes |
|---|---|---|
| Post | 500 | Default limit. Many instances raise it - check your server's about page. |
| Display name | 30 | Much shorter than the 64 graphemes Bluesky allows. |
| Profile note | 500 | Four profile fields are available, each with its own limit. |
| Content warning | 500 | Warning text has its own budget, separate from the post body. |
YouTube limits are generous in the body but ruthless in the title, because the title is what gets truncated in search results and suggested feeds.
| Field | Limit | Notes |
|---|---|---|
| Video title | 100 | Keep titles under 70 characters so they survive truncation in search and on mobile. |
| Description | 5,000 | Only the first 100 to 150 characters appear above the Show more link. |
| Tags (total) | 500 | Counts all tags combined, including the commas between them. |
| Comment | 10,000 | Comments on videos and community posts share this ceiling. |
Messaging limits are about delivery rather than display. SMS is the strict case: a single non-Latin character flips the encoding and drops the segment size from 160 to 70.
| Field | Limit | Notes |
|---|---|---|
| Single SMS (GSM-7) | 160 | Multi-part messages use 153 characters per segment. |
| Single SMS (UCS-2) | 70 | Multi-part messages use 67 characters per segment. |
| Field | Limit | Notes |
|---|---|---|
| Message | 65,536 | Technical ceiling. Very long messages are often rejected in practice. |
| Status / About | 139 | One of the tightest fields in the app. |
| Group subject | 25 | Shorter than most people expect for a group name. |
| Group description | 512 | Shown to members on the group info screen. |
| Field | Limit | Notes |
|---|---|---|
| Message | 40,000 | Long messages collapse behind a Show more link. |
| Channel topic | 250 | Shown in the channel header on desktop. |
| Channel purpose | 250 | Displayed in the channel details panel. |
| Custom status | 100 | Emoji count toward the limit alongside the text. |
Ad and store limits are hard cut-offs. Text that exceeds them is usually rejected at review rather than truncated, which is why these fields need to be checked before submission.
| Field | Limit | Notes |
|---|---|---|
| Headline | 30 | You can supply up to 15 headlines per responsive search ad. |
| Long headline | 90 | Used in larger native placements only. |
| Description | 90 | You can supply up to 4 descriptions per ad. |
| Sitelink text | 25 | Sitelink descriptions are limited to 35 characters each. |
| Display path | 15 | Two path fields, 15 characters each. |
| Field | Limit | Notes |
|---|---|---|
| Title tag | 60 | Google truncates around 580 pixels on desktop. |
| Meta description | 155 | Roughly 920 pixels. Google often rewrites it anyway. |
| H1 heading | 70 | No hard limit, but long H1s dilute keyword focus. |
| URL slug | 75 | Shorter slugs are easier to share and index. |
| Field | Limit | Notes |
|---|---|---|
| Subject line | 60 | Desktop clients show roughly this much before truncating. |
| Mobile (Gmail iOS) | 35 | The narrowest common window - write for this one. |
| Preheader text | 100 | Roughly 40 to 100 characters depending on the client. |
| Sender name | 30 | Displayed before the subject in most inboxes. |
| Field | Limit | Notes |
|---|---|---|
| App Store name | 30 | Indexed by search. Changing it requires a new version. |
| App Store subtitle | 30 | Also indexed, and shown under the name in results. |
| Keyword field | 100 | Comma separated, no spaces. Do not repeat words from the name. |
| Google Play title | 50 | More generous than Apple, but truncation still applies. |
| Play short description | 80 | Shown above the fold on the listing page. |
Marketplace limits are tied to search. A title that runs long gets cut in the listing grid, so the effective length is shorter than the stated maximum.
| Field | Limit | Notes |
|---|---|---|
| Listing title | 140 | Front-load the search phrase; only part shows in grid view. |
| Tag | 20 | Up to 13 tags per listing. Multi-word tags work best without spaces. |
| Listing description | 13,000 | The first 160 characters carry the most search weight. |
| Shop title | 40 | Shop titles can only be changed a limited number of times. |
A counter that reports raw string length will disagree with almost every platform on this list, because each one applies its own weighting rules before deciding whether your text fits.
X wraps every URL through its own shortener, so any link is charged 23 characters regardless of how long it really is.
Emoji outside the basic Latin range are counted as two characters on X, Instagram and most social platforms, not one.
A flag or a family emoji is one character on Bluesky even though it is built from several code points.
One character outside the GSM alphabet switches the whole message to UCS-2 encoding and halves the segment size.
Some platforms count CJK per character and others per byte, so a Chinese caption can hit a limit far sooner than English of the same visual length.
Among the social networks covered here, X (Twitter) has the smallest free posting limit at 280 characters. Google Ads headlines are tighter still at 30 characters, and App Store names are capped at 30 as well, but those are ad and store fields rather than posts.
Yes. Every platform counts spaces, punctuation and line breaks as characters. The exception is weighting: X charges a flat 23 characters for a link regardless of its real length, and most emoji count as two characters rather than one.
Usually two. Most emoji sit outside the basic Latin range and are counted as two characters by X, Instagram and similar platforms. SMS is stricter: adding a single emoji can switch the whole message from GSM-7 to UCS-2 encoding, cutting the per-segment limit from 160 characters to 70.
Because the visible limit is often shorter than the technical one. Facebook technically accepts 63,206 characters but the feed collapses long posts behind a See more link. Instagram captions are cut in the feed at roughly 125 characters, even though the limit is 2,200. Optimising for the visible cut-off matters more than staying under the maximum.
They can. X Premium accounts can post up to 25,000 characters while free accounts stay at 280. Some limits differ by app version or roll out gradually by region, and CJK characters are sometimes counted differently depending on the platform. Treat every number here as the common case and confirm inside the app for time sensitive work.
Yes. On Instagram, TikTok and LinkedIn, hashtags are part of the same character budget as the caption text. Instagram additionally caps a post at 30 hashtags regardless of how many characters they use.
Often enough that any static list goes stale. Platforms adjust limits quietly, and rollouts mean two accounts can see different numbers on the same day. This page is rebuilt from a single data file with a reviewed date, and the changelog records every update we make.
No. Every counter on this site runs in JavaScript inside your own browser. Nothing you paste is transmitted, stored or logged.
Paste once and CharLimits measures the same text against all 20 platforms using each one’s own counting rules. Nothing leaves your browser.
Compare limits across every platform See recent limit changes