You probably don’t spend much time thinking about the punctuation in your website’s URLs, but you should.
Something as small as using a hyphen instead of an underscore can influence how search engines interpret your content. And when you’re investing in professional SEO service, every detail counts, especially the way your URLs are structured.
The conversation around hyphens versus underscores in URLs has been going on for years in SEO circles. But if you’re looking for a definitive answer about which one performs better and why it matters, this guide is for you.
(Digital Buggu/pexels)
What’s the Difference Between Hyphens and Underscores in URLs?
On the surface, hyphens (-) and underscores (_) might seem interchangeable. You use both of them to separate words when spaces aren’t allowed, so why should it matter which one you pick?
It matters because search engines and humans interpret them differently. When you use hyphens in URLs, search engines like Google treat them as word separators. For example, a URL like yourdomain.com/seo-tips-for-beginners is recognized as five distinct words.
On the other hand, underscores aren’t treated the same way. A URL like yourdomain.com/seo_tips_for_beginners is typically read by search engines as one long word—seotipsforbeginners. This makes it harder for algorithms to understand what your content is actually about. And if Google struggles to make sense of your URL, that ambiguity can hold back your page from ranking well.
From a human perspective, hyphens are also easier to read. You want users to glance at your URL and instantly recognize what it’s about. Underscores, particularly in underlined links, can even become invisible to the eye, leading to potential confusion or misclicks.
What Does Google Recommend?
Let’s cut right to it. Google officially recommends using hyphens instead of underscores in URLs. This guidance comes directly from Google’s guidelines for developers1 and has been consistent for years.
The reason is simple: hyphens enhance readability for both users and search engines. By making each word in your URL clear and distinct, you’re improving clarity and reinforcing keyword signals. Since Google aims to serve users the most relevant content, helping the search engine understand your pages more easily can only work in your favor.
You might be thinking, “If underscores still technically work, do I really need to change anything?” The answer depends on your situation. If you’re launching a new website or creating new content, use hyphens from the start. But if you already have a site filled with URLs using underscores, the answer is more nuanced. Let’s walk you through it.
When Should You Change Existing URLs?
If your website already uses underscores, you may wonder if switching to hyphens will magically boost your SEO rankings. Unfortunately, it’s not that simple.
Changing URLs affects more than just visibility. It also impacts existing backlinks, user bookmarks, and indexed pages. Unless you have a 301 redirect plan in place, switching URLs without care could lead to broken links, crawl errors, and a drop in rankings. In many cases, the risk of changing established URLs outweighs the reward, especially if those URLs are already ranking and bringing in traffic.
However, if your site is underperforming, and poor URL structure is part of the reason, it might be worth evaluating a site-wide update. Just make sure you’re redirecting every old URL to the new one and updating internal links accordingly. This ensures that search engines transfer the ranking value from the old pages to the new ones without disruption.
If you’re building out new sections of your site, launching new product pages, or creating blog content, that’s where you have the opportunity to apply best practices. Use hyphens moving forward and avoid introducing underscores in any new URLs you create.
User Experience Matters in SEO, Even in URLs
You already know that SEO isn’t just about satisfying algorithms. It’s also about creating a better experience for your visitors. When users click on a search result, they see the title tag, meta description, and the URL. If your URL is clean, simple, and easy to interpret, it reinforces the idea that your content is organized and trustworthy.
Imagine searching for a guide on beginner SEO tips and seeing two results:
- yourdomain.com/seo-tips-for-beginners
- yourdomain.com/seo_tips_for_beginners
Which one looks more legitimate to you? The first option is not only easier to read, but it also aligns with what users expect to see. The second one looks less polished, and that perception can affect click-through rates.
In industries where trust is everything—think legal services, healthcare, or financial consulting—your URL structure can even play a small but meaningful role in building credibility with your audience. It’s not just about rankings. It’s about how users perceive your brand.
How URLs Impact Keyword Targeting
Keywords still play an important role in your SEO success. And while Google doesn’t rely solely on URL keywords to rank your pages, they’re still a ranking factor—albeit a minor one.
If your URL includes keywords that match the searcher’s intent, you reinforce the relevance of your content. For example, a URL like yourdomain.com/affordable-seo-services gives Google a strong signal that the page is about low-cost SEO offerings. That same phrase with underscores weakens the signal because Google reads it as one unbroken term.
The difference might be subtle in the short term, but over time, especially when competing in crowded niches, these small factors compound. If you’re targeting multiple long-tail keyword variations, hyphens can help your URLs support those efforts more effectively.
Technical SEO and Hyphen Use
From a technical perspective, search engines crawl your website by following internal and external links, analyzing each URL along the way. When URLs are clear and well-structured, they help improve crawl efficiency. Hyphens serve as visual and semantic cues for both search engines and users, aiding the indexing process.
Moreover, if your content is shared on social media, linked from third-party websites, or emailed between colleagues, a hyphenated URL ensures better interpretation. Some older systems don’t handle underscores well in links, leading to broken or misread URLs. In contrast, hyphens are universally recognized, stable, and reliable.
When you’re setting up canonical tags or creating sitemap entries, hyphenated URLs also improve consistency across your technical setup. Every element of your site works better together when your URL structure is predictable and standardized.
SEO-Friendly URL Best Practices
Using hyphens is just one piece of the puzzle. While you’re focused on structuring your URLs correctly, it helps to keep a few other best practices in mind:
- Keep your URLs short and relevant. Avoid stuffing them with too many keywords.
- Remove unnecessary parameters or session IDs unless absolutely required.
- Use lowercase letters to avoid case sensitivity issues with certain servers.
In addition to reinforcing your SEO strategy, these practices contribute to better usability and fewer technical issues in the long run. You don’t want your users—or Googlebot—struggling to interpret your URLs.
Hyphens Win for Both SEO and Clarity
If you’re serious about improving your website’s SEO, the small things matter. Choosing hyphens over underscores may seem trivial at first glance, but it affects everything from how search engines interpret your content to how users perceive your brand.
So, what should you do? Going forward, always use hyphens in your URLs. If you’re planning a redesign, launching a new blog, or building an e-commerce catalog, now is the time to lock in this standard. It sets the stage for better indexing, improved keyword recognition, and stronger user trust.
If you’re unsure whether your current URL structure is holding you back, don’t leave it to guesswork. Partner with a reputable SEO agency that can audit your site, guide you through technical improvements, and ensure every page, from the URL to the content, supports your growth goals.
Because when it comes to SEO, the smallest changes can lead to the biggest wins. And that starts with choosing the right characters in your URLs: hyphens, not underscores.
If you want to learn about what other small changes can make a big difference, our Salt Lake City SEO agency, SEO National, is happy to help you. Reach out today.
1https://developers.google.com/search/docs/crawling-indexing/url-structure