Localization testing

Localization testing image

What is localization testing?

Localization testing checks if software works correctly for specific regions, languages, or cultures. It confirms that translations, date formats, currencies, and UI layouts function properly for users in different locations.

Do you have any examples of localization testing?

Localization testers often check translated content, regional formatting, and cultural “appropriateness”. They verify elements like date formats, currency symbols, right-to-left text support, and localized images. 

For example, for an e-commerce site expanding to France, testers might make sure prices show in euros (€), French translations read naturally, and legal disclaimers meet local regulations.

Why is localization testing important?

Users in different regions need a seamless, culturally appropriate experience. Poorly localized software confuses users, creates usability problems, or offends through incorrect translations or culturally insensitive content. Good localization also helps businesses comply with regional laws.

What challenges exist in localization testing?

Managing multiple language versions, maintaining context in translations, and testing across different devices and systems create difficulties. Automated translation tools often miss language nuances. Solutions include hiring native-speaking testers, using specialized testing tools, and creating structured test plans.

What is Localisation Testing?

Localisation testing is the process of confirming that an application behaves as expected in each supported region. These regions could be broad — such as an EU-wide version of a site — or highly specific, like a custom landing page designed only for visitors from a single city.

How does a website know where the user is?

There are two main methods:

  • IP Geolocation
    The website looks up the visitor’s IP address in a geolocation database to estimate their location. These databases are generally very accurate at the country level, and can sometimes narrow down to the city — though with less reliability. This method requires no input from the user.

  • Browser Location API
    Modern browsers can provide precise location data using signals like GPS, nearby Wi-Fi networks, or cell towers. Unlike IP geolocation, this usually requires the user’s explicit permission before sharing.

How do websites change their content?

Websites typically use one of three approaches:

  1. Redirect to a country-specific TLD
    For example, a visitor from the UK navigating to example.com would be redirected to example.co.uk.

  2. Redirect to a region-specific path
    For example, a visitor from the UK landing on example.com would instead be taken to example.com/uk/.

  3. Serve location-specific content at the same URL
    In this case, the page at example.com shows different content depending on whether the visitor is in the UK or the USA — while keeping the same address.

Is this how websites decide what language to use?

Not always. While some websites rely on location to select a language, the better approach is to respect the user’s Accept-Language header. This allows people to choose their preferred language independent of their physical location. For example:

  • A user in the UK may prefer to browse in French.

  • A user in France may prefer to browse in English.

What sort of content is localised?

The specifics depend on the site, but common examples include:

  • Displaying GDPR cookie banners to users in Europe, but not elsewhere.

  • Showing region-specific content (e.g. Netflix only lists shows licensed in that region).

  • Adjusting pricing to reflect local currencies and market expectations.

What are the key steps in localisation testing?

  1. Identify the regions that have unique content
    You can’t test what you don’t know to look for. Start by mapping out which versions of the site exist (country, region, or city level) and what differs between them.

  2. Decide how to access region-specific versions of the site
    Common solutions include using proxy servers, VPNs, or test hooks built into the application that let you simulate being in a different location.

  3. Test from each location
    Verify that the actual behaviour matches the intended behaviour for each region. Be mindful of edge cases — for example, location-specific changes accidentally breaking other parts of the site.

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