Running a multilingual banner campaign: a small-team workflow

A multilingual banner campaign runs smoothly when you do the work in one fixed order. Approve a single master banner, pick two or three languages from your own data, translate the approved master, have a reader of each language sign it off, resize the approved versions, name every file with a standard language code, point each ad at a landing page in the same language, and judge results per language only after the ad platforms have had time to settle. This guide gives each step an owner, an output and a rough time, with a naming convention, a review checklist and a tracking sheet you can copy.

Choosing which languages to launch first

Start from your own numbers, not from a list of the world's most spoken languages. Three places to look:

• Analytics. In Google Analytics, the Language dimension reports the language of a visitor's browser or device. A language that already brings visitors who rarely convert is a good candidate.
• Sales and support. Look at orders by country and at the languages customers already write to you in.
• What you can support afterwards. If nobody can answer an email in Polish, think twice before advertising in Polish.

For a small team, two or three languages is a sensible first wave. Every extra language multiplies files, reviews and landing pages, and splits the budget into smaller pieces.

How language targeting works in Google Ads

According to Google Ads Help, language targeting reaches people based on the languages they understand. Where they are is a separate matter, handled by location settings.

On the Display Network, where uploaded banners run, Google says it may look at the language of the pages or apps someone is viewing or has recently viewed. Its own example is a reader of Japanese cooking blogs who may later see Japanese ads on English-language sites.

Two details on that help page matter for planning:

• Google describes checking whether a person understands the language of both the creative and the landing page. A German banner that leads to an English page works against the system as well as the visitor.
• The page notes a change starting in September 2026. The campaign-level language setting is being removed from Search campaigns, where ads are matched on the language of the ad itself. For Performance Max, Google says the setting still applies to YouTube, Display, Discover and Gmail.

Nothing in that documentation says Google will translate an image you upload. Language settings decide who can see a banner, and supplying it in each language is your job.

How Meta handles language

The Meta Business Help Centre says that if you choose no language when creating an ad, Meta delivers it to people its systems predict can understand the language of your creative. It also documents dynamic language optimisation, where one ad carries a default language plus up to 48 others, each with its own headline, primary text and, optionally, image. Meta notes the feature is not available with every campaign setup.

The workflow, step by step

The times below are planning allowances for a team of two or three people, not benchmarks. One person can hold several roles.

Here is what each step involves.

1. Approve the master first. Every later change is multiplied by every language and size, so freeze the copy, the offer and the layout before translating anything.
2. Choose the languages and write them down as tags. Use the codes from the naming section below, so that everyone means the same thing by "Portuguese".
3. Write a one-page copy brief. List the brand and product names, URLs and prices that must stay as they are, describe the tone, and say whether prices or dates need local formats.
4. Translate the approved master. With the design file and a designer, replace the text layers. With only the exported image, you can translate a banner with BannerTranslate: up to five languages per banner from 46, each version at the banner's own pixel size and drawn in about a minute. The result is a flat image made by an AI model, which is exactly why step 5 exists. Other routes are set out in banner translation tools compared.
5. Review the wording before making sizes. A correction now touches one file. After resizing it touches every size.
6. Resize the approved versions. Take the sizes from the placements you have booked, starting from our lists of Google Display ad sizes and social media image sizes. In BannerTranslate you resize a banner in a separate run from translating, with up to five sizes per banner. A resized banner is recomposed for its new shape, so glance over the words once more.
7. Name, file and log. Rename files as they leave the tool, not next week.
8. Prepare the landing pages. This is often the slowest step, so start it alongside step 4.
9. Traffic the ads. Check each platform's file rules first. Google's specification for uploaded image ads on the Display Network lists GIF, JPG and PNG with a maximum size of 150 KB, so a WebP or a heavy PNG needs converting. See JPG, PNG or WebP for banner ads.
10. Measure per language, after the waiting period described further down.

A worked example makes the load visible. One master, three new languages and four sizes gives 4 language versions including the original, times 4 sizes, which is 16 files, three wording reviews and four landing URLs. Do this arithmetic before you promise a launch date.

One limit to plan around: BannerTranslate does not handle animated or HTML5 banners or video, which go back to the source files.

A file-naming convention that survives a busy week

Use one pattern for every file, with underscores between the parts:

campaign_size_language_version.ext

For the language part, use BCP 47 language tags, the standard that HTML and XML use to mark the language of content. The W3C's guidance is to keep a tag as short as possible: a language subtag on its own, with a region or script subtag added only when it distinguishes something you care about. By convention the language is lowercase, the region is uppercase and a script subtag starts with a capital, with hyphens between subtags. Every valid subtag is listed in the IANA Language Subtag Registry.

Three rules keep the convention honest:

• Underscores between parts, hyphens only inside a part. Language tags contain hyphens, so a hyphen separator would make fr-CA ambiguous.
• Write the tag, never "spanish" or "ES". The W3C gives es-ES for Spanish as spoken in Spain and es-419 for Latin America, and the tag records which one you actually made. If one French banner serves every French-speaking market, plain fr is correct.
• Raise the version number, never overwrite. And retire the word "final", which is never true.

The W3C notes that letter-casing in tags is only a convention, and advises a consistent policy wherever case matters, as it can in file names.

A review checklist for each language

Give the reviewer the copy brief, the original banner and the translated one side by side. Ask them to confirm each point:

1. The meaning and tone match the original.
2. Spelling, accents and characters are correct in every line, including the small print. Text drawn by an AI model can look right at a glance and still hide a wrong letter.
3. Brand names, product names, URLs, prices and numbers are unchanged, unless the brief says otherwise.
4. Nothing is clipped, overlapping or too small to read. Short strings grow the most: IBM figures reproduced by the W3C put average expansion at 200 to 300 per cent for English text of up to 10 characters translated into European languages. Our article on text expansion shows what to do about it.
5. For Arabic, Hebrew, Persian or Urdu, the text runs right to left and the layout still makes sense. See right-to-left banners.
6. The call to action matches the button on the landing page, and nothing in the image is unwelcome in that market, a topic covered in what changes besides the words.

Log the reviewer's name, the date and the verdict in the tracking sheet. An approval that lives only in a chat thread will be lost by Thursday.

Matching the landing page language to the ad

The click should land on a page in the language of the banner, with the same offer, price and call to action. As noted above, Google describes weighing the language of the landing page as well as the creative.

Give each language its own URL and tag it so that Analytics can tell the versions apart. Google's Analytics help says to always use utm_source, utm_medium and utm_campaign, and describes utm_content as the parameter for differentiating creatives, which makes it a natural home for language and size:

The same help page says parameter values are case sensitive and recommends lowercase. So write pt-br in a link even though the file name says pt-BR, and do it every time.

A simple tracking sheet

One row per file is enough to carry a small campaign from brief to report:

Filter on the Status column and you can see at once what is blocking the launch. Give one person ownership of the sheet, because a sheet owned by everybody is updated by nobody.

What to measure per language, and how long to wait

Decide the structure first. Google Ads Help advises a separate campaign when you need different settings such as budget or location targeting, which is usually true of different languages. It also recommends consolidating where you can, so stop at one campaign or ad set per language unless you have a reason to split further.

For each language, track impressions and click-through rate, cost per click, landing-page conversion rate and cost per conversion. Compare each language with its own target, not with its neighbours, because audiences and costs differ between markets.

Then wait. Both big platforms describe a settling-in period before results can be trusted:

• Meta says an ad set usually leaves its learning phase after about 50 results in the week following its last significant edit, and that editing during learning resets it. It also warns that with many ads and ad sets the system learns less about each one.
• Google says the Learning status on a bid strategy lasts no more than 7 days and that performance can take up to one to two conversion cycles to stabilise. After that, it suggests evaluating over two conversion cycles or a two-week window, whichever is longer.

A practical rule follows: set the review date before launch, make it at least two weeks out, and leave the ads alone until then. If a language cannot gather enough results on its share of the budget, move that budget to a stronger language.

For more depth, see how to translate a banner and how to resize a banner, or browse the resources hub.

FAQ

How many languages should a small team launch with?

Two or three is a manageable first wave. Each language adds files in every size, a review, a landing page and a share of the budget. Choose them from your own analytics, sales and support data, and add more once the first wave has reported.

Does Google Ads translate my banners for me?

Plan on supplying them yourself. Google's documentation on language targeting describes matching ads to the languages people understand, and nothing in it says an uploaded image will be translated. You need one banner file for each language you want to run.

Should each language have its own campaign?

Often, yes. Google Ads Help advises a separate campaign when settings such as budget or location targeting differ, and languages usually come with different markets and landing pages. On Meta, dynamic language optimisation can instead hold several languages inside one ad, where your account offers it.

How long should I wait before comparing results by language?

At least two weeks is a reasonable floor. Meta says ad sets usually stabilise after about 50 results in a week without significant edits, and Google suggests judging Smart Bidding over two conversion cycles or two weeks, whichever is longer. Low-volume languages may need longer.

Who should review a banner if nobody on the team reads the language?

Ask a colleague in another department, a reseller or customer in that market, or a freelance translator. Give them the checklist above and the copy brief so the review takes minutes. For legal or regulated wording, pay a professional.

Sources

• Google Ads Help, About language targeting - how languages are detected, the landing page check and the September 2026 change.
• Google Ads Help, Choose your location and language settings - location and language as separate settings.
• Google Ads Help, Organize your account with ad groups - a separate campaign when budget or location settings differ.
• Google Ads Help, About Smart Bidding learning - the 7-day Learning status, consolidation, conversion cycles and the evaluation window.
• Google Ads Help, Uploaded display ads specifications - GIF, JPG and PNG formats, the 150 KB limit and the ad sizes.
• Meta Business Help Centre, Advertising in multiple languages - delivery when no language is chosen.
• Meta Business Help Centre, Create an ad using dynamic language optimisation - up to 48 additional languages, per-language text and image, and availability limits.
• Meta Business Help Centre, About the learning phase - about 50 results in a week, and the effect of edits and ad volume.
• Google Analytics Help, URL builders - UTM parameters, utm_content for creatives, case sensitivity and lowercase.
• Google Analytics Help, Dimensions and metrics - the definition of the Language dimension.
• W3C Internationalization, Choosing a language tag - keeping tags short, casing conventions and the es-ES and es-419 examples.
• W3C Internationalization, Language tags in HTML and XML - subtag structure and examples such as fr-CA and zh-Hans.
• IANA Language Subtag Registry - the registered language, script and region subtags.
• W3C Internationalization, Text size in translation - average expansion figures for short English strings.