Reddit Ad Headline Character Limit: 300 Max, 45 Optimal

Reddit Ads Manager accepts headlines up to 300 characters for Promoted Posts, but the in-feed card truncates well before that. This page documents the hard limits, where text gets cut, and the practical ranges that survive Reddit's feed rendering.

Hard limits (Reddit Ads Manager, 2025):

• Promoted Post headline / title: 300 characters max, 1 character min
• Promoted Post body (text post): 40,000 characters
• Link post URL display: pulled from destination, not editable
• Image/Video ad CTA button: preset list (Learn More, Shop Now, etc.) — not free text
• Carousel card headline: 50 characters per card
• Carousel card description: 30 characters per card

Where headlines actually truncate. The 300-char cap is the API ceiling, not the display ceiling. On desktop feed view, Reddit shows roughly the first 80-90 characters of a Promoted Post title before clipping with an ellipsis. On mobile (where ~85% of Reddit ad impressions land), that drops to roughly 60-70 characters depending on device width and whether a thumbnail is rendered. Carousel headlines clip hard at the 50-character field limit — there is no overflow.

Why the 300 limit exists. Reddit inherited the limit from organic post titles, which share the same backend field. Organic titles were capped at 300 to prevent title-as-bodycopy abuse on text-heavy subreddits. Ads use the same constraint for parity, but the feed UI was never designed to render 300 characters of title text — hence the visual truncation gap.

Truncation behavior to know:

• Title overflow: silent ellipsis. No rejection, no warning. You'll only notice it in the live preview or after launch.
• Carousel headline overflow: rejected at upload. The form blocks save.
• Emoji: counted as 1 character in Reddit's UI counter, but render width is roughly 2x a Latin character — so emoji-heavy titles truncate visually sooner than the count suggests.
• Special characters (em-dash, smart quotes): counted as 1 character but pasted from Word/Google Docs sometimes import as multi-byte sequences. Retype in plain text if the counter looks off.
• RTL languages (Arabic, Hebrew): character count is accurate, but Reddit's feed renderer occasionally misaligns mixed LTR/RTL strings — keep CTAs in the body, not the title, for RTL campaigns.

Fitting copy inside the practical range. For Promoted Posts, target 40-80 characters. This range survives both desktop and mobile truncation, and matches the median length of organic post titles in most large subreddits — important because Reddit's algorithm and audience both penalize titles that read as ad-shaped.

Rules that hold up:

• Front-load the specific noun ("React deploys" not "a solution for developers").
• One claim per title. Reddit titles aren't sub-headed — there's no room for a setup-payoff structure.
• Skip brand name unless the brand is the value prop. Logo and domain already render below the title.
• Avoid title case. Lowercase or sentence case reads as native; title case reads as ad copy.
• No exclamation marks. They survive the character count fine but get downvoted in the wild.

Worked example — trimming a 112-char title to fit:

Original (112 chars): "Introducing the new and improved one-click deployment platform for React developers building modern applications"

First pass — strip filler (78 chars): "New one-click deployment platform for React developers building modern apps"

Second pass — front-load noun, drop redundancy (43 chars): "Finally: one-click deploys for React apps"

The 43-char version fits well inside mobile truncation, leads with the emotional hook ("Finally"), and names the audience ("React apps") in the visible window.

Example

A SaaS team running Promoted Posts in r/webdev shipped two title variants: "Stop manually deploying — automate your React pipeline in 4 minutes" (67 chars, full visibility on mobile) and "The complete guide to modern frontend deployment workflows for engineering teams" (82 chars, truncated to "...for engineering te..." on iPhone SE). The shorter, more specific variant drove materially lower CPC.

Questions