Demand Gen Copy Specs: Demand Gen Ad Copy Specs, Headline Character Limits and Ad Copy Generator
Google Demand Gen replaced Discovery campaigns and brought its own text asset sheet with it, and almost every mistake teams make writing for it comes from assuming the limits carried over from somewhere else. They did not. Demand Gen gives you a longer headline than Performance Max, takes fewer of them, and quietly drops a field that Discovery advertisers relied on for years. The numbers below come from Google's own Demand Gen asset documentation rather than from other agency spec sheets, which is worth saying because the one rule that actually blocks a complete Ad Strength rating is the one most spec sheets leave out. Generate a set of headlines and descriptions that already fit the limits at the top of the page, then use the table as the reference you check them against.
Flat pricing, no credits · Updated September 2026
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Direct answer
Google Demand Gen ads take headlines of up to 40 characters, with at least one headline of 30 characters or fewer, descriptions of up to 90 characters, and a business name of up to 25 characters. You can supply one to five headlines and one to five descriptions, and Google recommends five headlines and three descriptions. There is no long headline field in Demand Gen, which is the single biggest difference from Performance Max, where headlines are capped at 30 characters but a separate 90 character long headline exists. The call to action is automated and the final URL accepts up to 2,048 characters.
The problem
The character limits are trivial to look up and expensive to get wrong, because the cost never shows up as a copywriting problem. It shows up three weeks later as an Ad Strength rating that will not leave incomplete, or as a campaign that serves one headline out of five because the other four were written at a length the placement cannot use. A team running Performance Max and Demand Gen side by side almost always writes one set of headlines and pastes it into both. That produces Demand Gen headlines that are ten characters shorter than they needed to be, which sounds harmless until you remember these placements sit inside YouTube, Discover and Gmail feeds where the headline is most of the ad. Going the other way is worse: paste 40 character Demand Gen headlines into Performance Max and they are simply rejected. Then there is the volume problem. Google wants five headlines and three descriptions per ad, and it wants them different enough from each other that the system has something real to test. Multiply that across a product catalog, a few audience segments and a refresh cycle and copy stops being a writing task and becomes a production line, which is where most teams quietly give up and ship one headline repeated with the product name swapped.
How Adscreator handles it
Adscreator writes the text assets for a Demand Gen ad against these limits. Give it a product URL or a short description of the offer and it returns headline options inside the 40 character cap with at least one written under 30 so the Ad Strength requirement is satisfied, descriptions inside 90 characters, and a business name that fits 25, along with the on brand square and horizontal images the same ad needs. Because it returns a set of genuinely different variants rather than one line, you get the five headlines Google asks for instead of one written five ways, which is the difference between an asset pool the system can test and a pool that only looks full. Two boundaries are worth stating plainly. Adscreator produces static images and ad copy, so the video assets a Demand Gen campaign can also use are not part of what it makes, and it has no connection to your Google Ads account, so finished copy and images are pasted or uploaded into the campaign the way any asset is. The product is not open for purchase yet. Planned pricing starts at $39 monthly, flat, and you can join the waitlist from the panel above.
specs
Every Demand Gen text asset, with the exact character limit Google documents.
These are the text asset requirements from Google's own Demand Gen specs and format requirements documentation, verified in September 2026. Character limits are per asset, not totals. The recommended counts are Google's recommendations rather than hard minimums, but they are worth treating as targets, because Demand Gen assembles ads from the pool you supply and a thin pool limits what it can serve. The final row is included because its absence causes more confusion than any of the limits above it.
| Text asset | Character limit | How many you can supply | Required | What to watch |
|---|---|---|---|---|
| Headline | 40 characters | 1 to 5, Google recommends 5 | Yes | At least one headline must be 30 characters or fewer or Ad Strength stays incomplete |
| Description | 90 characters | 1 to 5, Google recommends 3 | Yes | Carries your long form message, because there is no long headline field in this campaign type |
| Business name | 25 characters | 1 | Yes | Use the name customers recognize; it will not wrap or resize |
| Call to action | Automated | 1 | Yes | Google selects the call to action rather than you writing one |
| Final URL | 2,048 characters | 1 | Yes | Check the assembled length once tracking templates and UTM strings are appended |
| Long headline | Not available | 0 | Not applicable | Demand Gen has no long headline field, unlike Performance Max, where it is 90 characters |
Limits are taken from Google's Demand Gen campaign specs and format requirements. The same page lists the image assets a Demand Gen ad needs alongside this copy: a 1:1 logo at a recommended 1200 x 1200 pixels, a 1.91:1 horizontal image at a recommended 1200 x 628, and a 1:1 square at a recommended 1200 x 1200, with one to twenty of each image type and three recommended. Demand Gen creative specs are identical whether you buy through Google Ads or Display and Video 360, so one asset set travels between both.
The 40 character headline that has to be 30
This is the rule that separates a spec sheet copied from another blog post from one that read the documentation. Google caps Demand Gen headlines at 40 characters, and nearly every published spec sheet stops there. The requirement underneath it is that at least one headline in the ad comes in at 30 characters or fewer, and if none does, the Ad Strength rating will not reach complete. The reason is structural rather than stylistic. Demand Gen serves into YouTube, Shorts, Discover and Gmail, and those surfaces do not all give a headline the same room. A placement that has space for roughly 30 characters needs at least one asset that fits, and if the pool you supplied is five headlines all written at 39 characters, the system has nothing to render there. The practical method is to write the short one first rather than last. Start with the 30 character version, which forces the message down to the offer and nothing else, then let the remaining four use the full 40 to add the qualifier, the proof point or the audience. Teams who write five long headlines and then trim one at the end usually produce a truncated version of a long line rather than a genuinely short line, and it reads that way in the feed.
Demand Gen and Performance Max are the two Google campaign types most often written as one
If you run both, this is where the hours go. The two campaign types look adjacent in the interface and share the same asset based logic, so the natural assumption is that a headline written for one works in the other. The limits say otherwise, and they diverge in a way that punishes copying in either direction. Demand Gen allows 40 character headlines and takes one to five of them, and asks that at least one be 30 characters or fewer. Performance Max allows 30 character headlines, takes three to fifteen of them, and asks that at least one be 15 characters or fewer. Descriptions are 90 characters in both, which is the one thing that does travel. The largest structural difference is the long headline: Performance Max has a 90 character long headline field and takes one to five, and Demand Gen has no equivalent at all. Move a campaign from Performance Max to Demand Gen and your long headlines have nowhere to go. Move copy the other way and every 40 character headline is rejected on entry. The workable approach is to write the Performance Max set first, because 30 characters is the tighter constraint, then expand the strongest lines to 40 for Demand Gen rather than writing two independent sets from a blank page.
Five headlines is a testing requirement, not a word count
Google recommends five headlines and three descriptions per Demand Gen ad, and the recommendation is routinely met in the most literal way possible: one headline, then four versions of it with the product name moved around. That satisfies the counter in the interface and defeats the point. Demand Gen assembles ads by mixing assets from the pool you supply and learning which combinations perform, which means the pool is the experiment. Five near identical headlines give the system five ways to say the same thing and no information about what actually moves your buyer. A pool worth testing varies the angle rather than the wording: one headline leads with the offer, one with the outcome, one with the specific number or timeframe, one with the objection, one with the audience named directly. The same logic applies to the three descriptions, and it matters more there because the description carries the weight the missing long headline used to. This is also the honest reason production tooling is worth having for Demand Gen specifically. Writing five genuinely distinct angles per ad is not hard once. It is hard across forty products and a monthly refresh, and that is the point where most asset pools quietly collapse back to one idea repeated five times.
what it uses
The features behind demand gen ad copy generator.
questions
Demand Gen ad copy generator: the questions people ask.
What is the character limit for Demand Gen headlines?
Demand Gen headlines are capped at 40 characters each, and Google requires that at least one headline in the ad is 30 characters or fewer. That second rule is the one that catches people. Write all five headlines at 38 or 39 characters and the ad still saves, but the Ad Strength rating will not reach complete, because some placements need a short headline to render. You can supply one to five headlines and Google recommends supplying all five.
How many headlines and descriptions does a Demand Gen ad need?
A Demand Gen ad requires at least one headline and at least one description, and accepts up to five of each. Google recommends five headlines and three descriptions. The recommendation is worth following, because the asset pool you provide is the pool the system mixes and matches from. One headline and one description is a valid ad, but it gives Google nothing to test and no way to adapt the ad to different placements across YouTube, Shorts, Discover and Gmail.
Does Demand Gen have a long headline?
No. Google's Demand Gen text asset requirements list a headline, a description, a business name, a call to action and a final URL, and there is no long headline field among them. This trips up advertisers moving from Discovery campaigns or from Performance Max, where a separate 90 character long headline does exist. If your best long form value proposition was living in a long headline, in Demand Gen it has to move into a description, which is also capped at 90 characters.
What is the Demand Gen description character limit?
Descriptions are capped at 90 characters each in Demand Gen. You can supply one to five and Google recommends three. Because there is no long headline field in this campaign type, the description carries the longer part of your message, so it is worth writing all three as genuinely different angles rather than as three edits of the same sentence. Treat one as the offer, one as the proof, and one as the objection you keep hearing from buyers.
How many characters is the business name in a Demand Gen ad?
The business name is capped at 25 characters and exactly one is required. It renders alongside the ad across Demand Gen placements, so it should be the name people recognize rather than a legal entity name padded out with an abbreviation. If your brand name does not fit in 25 characters, shorten it to the form customers actually use rather than truncating it mid word, because Google will not wrap or resize it for you.
Are Demand Gen character limits the same as Performance Max?
No, and they differ in both directions. Demand Gen headlines allow 40 characters and Performance Max allows 30, so Demand Gen copy pasted into Performance Max gets rejected. Performance Max has a 90 character long headline and Demand Gen has none. Demand Gen takes one to five headlines while Performance Max takes three to fifteen. Descriptions are 90 characters in both. Performance Max also asks that at least one headline be 15 characters or fewer, where Demand Gen asks for 30 or fewer.
Why is my Demand Gen ad strength incomplete?
The most common cause is that no headline is 30 characters or fewer. Google will accept headlines up to 40 characters, but it requires at least one short headline in the ad, and an asset pool written entirely at the maximum length leaves the rating stuck below complete. The other frequent causes are supplying fewer than the recommended five headlines and three descriptions, and supplying only one image ratio when the campaign can use square, horizontal and vertical assets.
What is the final URL character limit in Demand Gen?
The final URL accepts up to 2,048 characters and exactly one is required per ad. That ceiling is generous enough that it is rarely the constraint, but it matters when you are appending long tracking templates, UTM strings and click identifiers to a URL that already carries product path segments. If you are building URLs programmatically across a large catalog, check the assembled length rather than the base URL length.
▪ keep reading
The full asset sheet, including image ratios, logo rules, video limits and file sizes, is in Demand Gen ad specs. This page covers only the text assets; that one covers everything a Demand Gen campaign needs to publish.
To produce the creative rather than check a limit, Demand Gen ad maker covers building the images and copy together from one URL, and the ad copy generator covers how the copy itself is written.
For the same job on other Google surfaces, Google ad copy generator covers responsive search ad headlines and descriptions, and DV360 ad specs covers the display side, where Demand Gen inventory is bought through the same platform on a completely separate spec sheet.
▪ more use cases