Summary
While URL length itself isn't typically a primary driver of email deliverability issues, the consensus is that it can indirectly affect it in several ways. Key areas of concern include the potential for increased email size leading to clipping in email clients like Gmail, especially with the use of excessive HTML code. Long URLs combined with redirects or URL shorteners can sometimes trigger spam filters. Older browsers have limitations on URL length, requiring consideration for compatibility. The reputation of the URL and linked domain is also critical, as is maintaining clean and direct URLs for optimal deliverability and rendering. Expert opinions indicate that excessive URL length is less impactful than factors like domain reputation and the presence of redirects, but it's wise to minimize URL lengths where possible for best practice.
Key findings
- URL Length Not Primary: URL length itself is not typically the main factor affecting email deliverability, but it can contribute.
- Clipping Potential: Long URLs can increase overall email size, leading to message clipping in email clients like Gmail.
- Spam Trigger: Long URLs, especially with URL shorteners or numerous redirects, can sometimes trigger spam filters.
- Older Browser Limits: Older versions of Internet Explorer had limited URL length support.
- Reputation Matters: The reputation of URLs and linked domains is a critical factor for deliverability.
Key considerations
- Reduce Email Size: Minimize overall email size to avoid clipping; shortening URLs may help.
- Avoid Excessive Redirects: Avoid excessive URL redirects to ensure better deliverability and rendering.
- Use URL Shorteners Wisely: Use URL shorteners with caution; ensure the service is reputable to avoid spam filters.
- Test on Older Systems: If supporting older browsers, test URL lengths to ensure compatibility.
- Maintain Clean URLs: Maintain clean and direct URLs; avoid excessive or complex links.
What email marketers say
11 marketer opinions
While URL length is not typically a direct factor in email deliverability, it can indirectly affect it and email rendering in several ways. Long URLs can contribute to larger email sizes, leading to clipping in email clients like Gmail. They can also trigger spam filters, especially when combined with URL shorteners or redirects with poor reputation. Older browsers have URL length limits, and excessively long URLs can negatively impact user experience and SEO. Therefore, clean, concise URLs are preferable, and URL shortening services should be used cautiously.
Key opinions
- Clipping: Long URLs increase email size, potentially causing clipping in email clients like Gmail.
- Spam Filters: Long URLs, especially with URL shorteners or redirects, can trigger spam filters.
- Browser Limits: Older browsers have URL length limitations that can cause issues.
- SEO Impact: Shorter, descriptive URLs improve user experience and indirectly improve SEO by increasing click-through rates.
- Redirects and Reputation: The reason for URL length can matter. Explicit redirects and bad domain reputations can affect deliverability.
Key considerations
- URL Shortening: Use URL shortening services cautiously, as untrustworthy ones can negatively impact deliverability. Ensure that when shortening links that are trusted, or use a custom domain for link shortening that has a good reputation.
- URL Structure: Opt for clean, direct URLs over long, complex ones to reduce the risk of triggering spam filters and ensure deliverability
- Email Size: Minimize overall email size, including URL lengths, to prevent clipping issues.
- Browser Compatibility: Consider URL length limitations of older browsers, if supporting these.
- URL reputation: Always use trusted URLs with a good domain reputation to avoid deliverability issues.
Marketer view
Email marketer from Stack Overflow mentions that while HTTP protocol does not enforce maximum URL lengths, various browsers and servers do. Suggests keeping URLs under 2000 characters to avoid potential issues with older browsers and systems.
19 Feb 2025 - Stack Overflow
Marketer view
Email marketer from Email Geeks highlights to be mindful that the maximum length in some browsers is about 2000 characters, others are longer.
3 Dec 2024 - Email Geeks
What the experts say
3 expert opinions
Experts generally agree that URL length itself is not a primary factor affecting email deliverability. The presence of redirects, the domain's reputation, and overall email size are more significant concerns. While extremely long URLs can contribute to clipping issues, clean and reputable links are essential for optimal deliverability.
Key opinions
- URL Length Not Primary: URL length itself is not a primary driver of email deliverability issues.
- Redirects and Reputation Matter: Redirects within the URL and the domain's reputation are critical factors influencing deliverability.
- Clipping: Extremely long URLs can contribute to an email's overall size, leading to clipping.
Key considerations
- Check Domain Reputation: Ensure the linked domain has a good reputation to avoid deliverability problems.
- Minimize Redirects: Reduce the number of redirects within the URL to improve deliverability.
- Keep Emails Concise: Keep emails concise to avoid clipping issues; this includes shortening extremely long URLs when feasible.
Expert view
Expert from Spam Resource explains that there is no inherent deliverability issue with long URLs. The real problem lies if there are redirects in the URL or the domain has a poor reputation. In these cases, shortening the URL could help to mask these problems.
16 Aug 2022 - Spam Resource
Expert view
Expert from Email Geeks shares that she has not seen anything obvious that indicates URL length, itself, is a factor in delivery. Mentions there was a point where it seemed like long URLs might be a problem, but that was a long time ago. She has stopped looking at URL length in her audits because she found a lot of long URLs weren’t a problem. Mentions one company that still suggests shortening URLs as a way to improve delivery, but there doesn’t seem to be much evidence one way or another.
20 Nov 2023 - Email Geeks
What the documentation says
4 technical articles
Technical documentation indicates that while there's no inherent URI length limit, practical constraints exist. Long URLs can contribute to overall message size, potentially causing clipping in Gmail. Older browsers, such as Internet Explorer, had specific URL length limitations. Modern browsers generally support lengths up to 2000 characters, but testing on older systems is crucial if they are part of your target audience.
Key findings
- Gmail Clipping: Long URLs can contribute to overall message size, potentially leading to clipping in Gmail.
- No Inherent Limit: RFC 7230 specifies no predefined URI length limit, but practical limitations exist.
- Historical Limits: Older versions of Internet Explorer had a URL length limit of around 2048 characters.
- Browser Support: Modern browsers generally support URIs up to 2000 characters.
Key considerations
- Reduce Email Size: Minimize overall email size to prevent clipping, and shortening long URLs may help.
- Test on Older Systems: If supporting older browsers, test URL lengths to ensure compatibility.
- System Constraints: Be aware of practical limitations due to system constraints, even without protocol-defined limits.
Technical article
Documentation from RFC 7230 (HTTP/1.1) specifies that there is no predefined limit to the length of a URI. Servers and user agents should be able to handle URIs of any length, but practical limitations may exist due to system constraints. This relates to how email clients handle links.
19 May 2024 - RFC 7230
Technical article
Documentation from Mozilla Developer Network states that most browsers support URIs up to 2,000 characters in length. Older browsers, however, may have stricter limits. It is always important to test on older browsers if you support them.
11 Jan 2023 - Mozilla Developer Network (MDN)
