Why character counts decide whether your ad works
A Facebook ad has only a few seconds to land its message as someone scrolls. If the copy runs long, Facebook doesn’t shrink it to fit — it cuts it off, hiding everything past the truncation point behind a “See more” link that most people never tap. A perfectly argued primary text means nothing if the call-to-action sits in the half no one reads. Counting characters before you publish is the difference between an ad that communicates and one that trails off mid-sentence. The Facebook Ad Text Counter makes those counts visible as you write, but it helps to understand what each limit is and why it exists.
The three text fields
A standard Facebook ad has three editable text fields, each with its own limit and its own behaviour.
Primary text — limit ~500, recommended ~125
Primary text is the body copy that sits above the image or video. Ads Manager lets you enter a long block — around 500 characters in practice — but Facebook typically truncates it after about 125 characters on mobile, appending “See more.” That recommended figure, not the hard cap, is the number that matters. Everything essential — your hook, your offer, your call-to-action — should fit inside the first 125 characters. Use the rest, if at all, for supporting detail that’s nice to have but not load-bearing. The Facebook Ad Text Counter turns the field amber once you pass 125 so you know you’re into truncation territory.
Headline — limit ~100, recommended ~40
The headline appears in bold beneath the image, next to the call-to-action button. It’s the most durable piece of text in your ad: it shows in almost every placement and is often the first thing a scanner reads. The hard limit is around 100 characters, but Facebook recommends keeping it near 40 so it doesn’t wrap or clip on smaller screens. A tight, benefit-led headline (“Save 40% This Week”) almost always beats a long descriptive one.
Description — limit ~30, optional
The link description is the small grey line under the headline. It only appears in some placements, and when it does, you have roughly 30 characters to work with. Because it’s both optional and easily cut, treat it as a bonus rather than a place for important information. A short reinforcement of the offer (“Ends Sunday”) is ideal.
Where ads get truncated
Truncation isn’t one fixed point — it depends on placement, device, and how much other content surrounds the ad. The general pattern:
- Feed (mobile): primary text clips around 125 characters; headline shows roughly one line.
- Feed (desktop): a little more primary text is visible, but the same front-loading rule applies.
- Stories and Reels: very little text shows over the media; the headline and button dominate.
- Right column (desktop): tight space; headline is king and primary text is minimal.
Because the same creative runs across all of these, write for the tightest case. If your message survives the mobile feed’s 125-character clip, it survives everywhere.
Writing copy that fits
Fitting Facebook’s limits is a craft, not just a trimming exercise. A few habits help.
Front-load the hook
Put the single most important idea first. Assume everything after the first sentence may be hidden. “Cut your electricity bill by 30%” works because the value is immediate; “We’re a family business that has, for over a decade…” buries the point.
Lead with benefits, not features
A character limit forces prioritisation, and benefits win. “Sleep better tonight” outperforms “Memory-foam mattress with seven-zone support” in a tight space because it states the outcome the reader cares about.
One call-to-action
With limited characters, a single clear instruction beats a list. “Shop the sale” or “Book a free demo” gives the reader one obvious next step. Pair it with the matching button in the ad.
Use emojis sparingly
Emojis count as characters and take visual space, but a single well-placed emoji can draw the eye. The Facebook Ad Text Counter counts them by code point, so you can see their cost. One is a highlight; five is clutter.
Count characters the way the platform does
Not every “character” is counted the same way. Plain letters and digits each count as one, but emoji, accented letters, and some symbols are built from multiple underlying code units — and a naive counter can report them as two or three characters when the platform treats them as one. The Facebook Ad Text Counter counts by Unicode code point, which matches how Facebook measures your copy, so the number you see is the number that counts. If you want the deeper background on why character counting is trickier than it looks, the guide on character counting walks through code points, whitespace, and the common pitfalls. Getting this right matters most in the 30-character description, where a single miscounted emoji can be the difference between fitting and being cut.
Test, then test again
No guide replaces testing against your own audience. Facebook’s strength is that you can run several versions of the same ad and let performance pick the winner. Write two or three variants — a short punchy primary text against a longer detailed one, a benefit headline against a curiosity headline — and compare. The character counter keeps each version inside the limits so the test is about the message, not about which one happened to get truncated.
Bringing it together
Facebook’s character limits exist because attention is scarce and screen space is tight. Treat the recommended lengths — not the hard caps — as your real budget: about 125 characters of primary text, 40 for the headline, 30 for the description. Front-load the hook, lead with benefits, keep one call-to-action, and check every field before you publish. Paste your copy into the Facebook Ad Text Counter, watch the live preview, and trim anything flagged before Facebook trims it for you.