Here's why your i18n is underperforming (and how to fix it)

“Good” i18n isn’t good enough

Optimized internationalization (i18n) is the process of designing software so it can support any language or region without rewriting code. It lays the foundation for effective localization (l10n) by ensuring your product can handle diverse text, formats, rules, and layouts. Without it, localization and translation can be slow, inconsistent, and hard to scale. But, despite the growing adoption of i18n, many businesses still struggle with delivering a smooth, localized experience for their customers. 

Why does this happen? 

The root cause of underperforming i18n isn’t always what you think. For many companies, it’s not the architecture or the tools—its the approach. Too many teams treat internationalization as an afterthought instead of a priority, getting stuck in a reactive cycle. 

When it’s time to localize, this reactive approach catches up with you. Expanding to new audiences becomes a cumbersome and fragmented process. Performance bottlenecks, negative user experiences, and missed deadlines become the norm. Ultimately, underperforming internationalization doesn't just slow down engineering, it impacts every facet of your business.

Some common problems include:

• Duplicated efforts: When you put i18n on the back burner, you’re inadvertently creating hundreds (if not thousands) of hours of costly rework for your teams. Without an i18n-first strategy, teams may hard code strings or build features that aren’t designed to scale across languages. During localization, you end up translating the same strings multiple times, troubleshooting broken code, and creating a patchwork of quick fixes that don’t build long-term value. 

• Manual processes: Manual processes add time and introduce risk to content translation. Setting up automation early in development streamlines workflows and minimizes manual intervention.  

• Poor user experience: Like it or not, UX can make or break customer engagement and conversion rate. Optimizing UX for multilingual audiences at scale is even more challenging. Underperforming i18n can lead to untranslated strings, inconsistent translations, and even broken code when you reach the localization stage. 

• Slow load times: Underperforming i18n leads to bloated builds and sluggish load times. Oversized bundles, inefficient memory use, and a lack of integrations all contribute to longer loading, ultimately frustrating users and driving them away. 

When Mailgun and Mailjet by Sinch were looking to scale their manual localization process, they turned to Smartling. By integrating Smartling with Contentful, Zendesk, and Figma, the teams streamlined their workflows while improving translation quality, saving more than 2,500 manual hours and $180,000 in just one year. Read the full story here.

Best practices for i18n performance optimization

Internationalization is the foundation for any product going global. And the sooner you implement best practices, the fewer issues you’ll face down the road. 

To avoid the problems that come from underprioritizing i18n, consider implementing:

• Bundle size optimization: Bundle size is a critical factor in product performance; the larger the bundle size, the longer it takes to load. Beyond load times, large bundles consume more memory, which can slow runtime, increase crashes, and cause layout issues. To optimize bundle sizes, start by splitting up translation files so only the relevant locale loads when needed. Lighter formats like JSON and compressed files also help reduce transfer size and speed up delivery. 
• Lazy loading: The lazy loading technique is a necessity for any large project. When you implement lazy loading, you only load the resources and code when you need them instead of at application startup—dramatically reducing load times and memory usage. Lazy loading enhances scalability and flexibility, enabling you to add new features, languages, or components without impacting performance. 
• Integration and automation: Incorporating a TMS like Smartling with your tech stack helps you streamline your i18n and l10n efforts by automating workflows, eliminating human errors, accelerating deployment, and providing actionable insights. 

i18n performance benchmarks

Optimizing i18n is an ongoing process. Continuous improvement is key to maintaining performance. Measuring performance benchmarks provides visibility into your i18n and l10n efforts and helps developers prioritize improvements. With that in mind, key performance indicators (KPIs) like the i18n library speed, translation data loading speed, automation effectiveness, engagement rate, and error rate can help you better understand the impact of your localization efforts. 

Ready to optimize your i18n? Book a meeting with our team.