How to localize ad creative with AI

Key takeaways

• Localizing an ad means adapting the copy, the on-image text, the units, the references and sometimes the people and settings for each market.
• Translated copy grows, often by half or more on short headlines and calls to action, so the layout has to make room for it.
• Regenerating the creative around the new copy keeps the text part of the design. On Melius, one brief to Mel produces every market's version from the source ad.
• Ad platforms now translate inside their own tools, but each one only works on that platform's own ads.
• A native speaker reviews every version before launch. AI gets most of the way, and the last part is tone, claims and cultural fit.

Localizing ad creative with AI

To localize an ad with AI, have a language model translate and adapt the copy for each market, regenerate the image or video around the new copy so the text sits inside the design, swap units, currency and cultural references, and have a native speaker review each version before launch. Translation is the easy part. The work is in the parts of the ad that don't read as words: the length of the headline in German, the holiday in the background, the price in dollars.

It's worth doing. In CSA Research's 2020 survey of 8,709 consumers in 29 countries, 76% preferred to buy products with information in their own language, and 40% said they'd never buy from websites in other languages. On Melius, one brief to the agent Mel turns a finished ad into a version for each market on the same canvas.

What localization changes besides the words

• The copy itself. A slogan that works in English may need rewriting rather than translating, which localizers call transcreation. Puns and idioms rarely survive a literal pass.
• Text length. Translations from English into European languages run longer, and short strings grow most. IBM figures cited by the W3C put English text of up to 10 characters at 200% to 300% of its original length once translated into European languages, and that's the size of a call to action.
• Character width and direction. Google Ads counts each Chinese, Japanese or Korean character as two toward its limits, and Arabic and Hebrew layouts read right to left, so the layout mirrors.
• Units, currency and dates. Miles become kilometers, Fahrenheit becomes Celsius, and a price has to be a real local price.
• References and imagery. A Thanksgiving table, a baseball cap or an American kitchen can make an ad read as foreign. The setting and sometimes the people change along with the copy.
• Legal rules. Some markets regulate ad language directly. Under France's Toubon law, foreign-language wording in an ad must also appear in French, at least as legible as the original.

How to localize an ad on Melius

Start from a finished ad, or from the canvas that made it, so the localized versions inherit the same layout, product and look.

1. Open the source ad's canvas and group it. Select the ad, or the whole workflow behind it, and group it with Cmd+G so Mel treats it as one unit.
2. Brief Mel with every market at once. List the markets and languages, and say what changes besides the copy: units, currency, seasonal references and the setting.
3. Put the fixed rules in your brand anchor. Lines such as "our brand name never gets translated" or "use the formal you" belong in the brand anchor text node, so they apply to every market without being repeated in each brief.
4. Review each version with a native speaker. Fix a single line by editing that node's prompt and rerunning only that node.

Localizing video ads

Video has two extra layers: the voiceover and, for anyone speaking on camera, the lip movement. Melius has ElevenLabs voice models, including Eleven v4, which speaks more than 90 languages, and lip-sync models such as HeyGen Lipsync, Sync Lipsync v3 and Kling Lipsync. You can generate a translated voiceover on an audio node and run it through a lip-sync model on the same canvas, then have a native speaker listen to the result as well as read the script. For more on voice models, see our guide to AI text-to-speech voiceover.

Short clips are easier. Kling Lipsync, for example, takes video of two to 10 seconds and audio of two to 60 seconds, so a 30-second spot is synced in parts.

Localization tools inside the ad platforms

The major ad platforms now translate inside their own tools. They're useful for one platform at a time, with less control over the result.

• Meta. Advantage+ creative can translate an ad's primary text and headline for people in your audience who speak other languages, and in 2026 Meta added translation for on-image text and video voiceovers. Translation can be switched on by default, so check which languages are selected before launch.
• TikTok. Symphony Creative Studio translates and dubs videos with lip-sync and subtitles, free for TikTok for Business users.
• Google Ads. The AI campaign localization tool launched in beta for Search campaigns, with Performance Max support announced from September 2026. It translates from US English into 10 languages and creates each as a new campaign, paused until you review it. It doesn't convert currency: a $100 budget stays a $100 budget.

Where AI localization goes wrong

• Garbled text in the image. Image models still misspell, especially in small type and in less common scripts. Google says Nano Banana Pro may make grammar mistakes or miss cultural nuance in multilingual text. Zoom in on every line before it ships.
• Copy localized, imagery left alone. A perfectly translated headline over an American suburb still reads as an import. Brief the setting as well as the words.
• Brand terms translated. Product names, trademarks and certification marks get translated unless something says they can't be. A glossary or a line in the brand anchor fixes it once.
• Correct language, wrong voice. The grammar can be right while the tone is too formal, too casual or makes a claim that's regulated in that market. This is what the native-speaker review is for.

After localization, resize

Each market's ad then needs every placement size. Our guide to resizing ads with AI covers turning one finished ad into the feed, Stories and banner formats, so a five-market campaign doesn't mean laying out 15 files by hand. To test several versions of the same ad in each market, see our roundup of AI video ad creative variants tools.

Frequently asked questions

Taking a campaign into new markets? See Melius for marketers and brief Mel with your source ad and the list of markets.