Summary
The problem of random characters appearing in email click tracking URLs arises from a confluence of factors. Encoding issues (especially with special characters like '&'), inconsistent HTML rendering across email clients, problematic URL rewriting features in email platforms, and formatting discrepancies in plain text versions of emails all contribute. URL length limitations and improperly formed UTM parameters can also lead to URL corruption. Diagnosing these issues often involves inspecting the email's code, testing across various email clients, validating HTML and URL structures, and ensuring correct encoding. While not usually a deliverability issue directly, these URL modifications can negatively impact tracking and user experience.
Key findings
- Encoding Problems: Incorrect encoding of URLs, particularly special characters, is a common cause.
- Client Rendering Variations: Different email clients render HTML and interpret URLs in varying ways.
- Plain Text Issues: Plain text versions of emails can introduce formatting problems, such as wrapping URLs in brackets.
- URL Rewriting: URL rewriting features in email platforms can sometimes corrupt URLs, especially with aggressive encoding.
- UTM Parameter Errors: Improperly formed UTM parameters can lead to unexpected characters or broken links.
- URL Length Limits: Exceeding URL length limits can cause truncation and data corruption.
- Client Specific Code: A small number of clients may cause the problem due to how the clients render HTML.
Key considerations
- Validate HTML: Ensure HTML is properly formatted and free of errors.
- Proper Encoding: Use URL encoding tools to correctly encode special characters and parameters.
- Plain Text Review: Review the plain text version of emails to ensure URLs are correctly formatted.
- Test Across Clients: Thoroughly test emails across multiple email clients and devices.
- Concise URLs: Keep URLs concise and consider using URL shortening services.
- UTM Validation: Validate UTM parameters to ensure they are properly formed and supported.
- Encoding Settings Check: Review encoding settings within your email service platform and URL rewriting features.
- ASCII Dump Check: Perform an ASCII dump of the email source code to check for any hidden characters or encoding issues.
What email marketers say
8 marketer opinions
Random characters appearing in email click tracking URLs stem from a variety of sources. These include issues related to email client interpretation, encoding problems, and HTML formatting errors. Specifically, email clients might misinterpret URLs with special characters, and poorly formatted HTML can introduce unexpected characters. Plain text versions of emails, when not properly formatted, may wrap URLs in brackets, causing adjacent text to be captured. Encoding URL parameters incorrectly, especially special characters like '&', and utilizing problematic UTM parameters also contribute. Proper testing and validation are crucial to mitigate these issues.
Key opinions
- Client Interpretation: Email clients can misinterpret or modify URLs, especially those with special characters.
- Encoding Issues: Incorrect URL encoding, particularly of special characters like '&', can break URLs.
- HTML Formatting: Poorly formatted HTML can introduce unexpected characters in URLs.
- Plain Text Formatting: Plain text versions of emails may wrap URLs in brackets, capturing adjacent text.
- UTM Parameters: Improperly formed UTM parameters can cause issues with URL tracking.
Key considerations
- Proper Encoding: Ensure all URLs, especially those with parameters, are correctly encoded using URL encoding tools.
- HTML Validation: Follow proper HTML coding practices to avoid unconventional characters and formatting errors.
- Plain Text Check: Always check the plain text version of emails to ensure URLs are correctly formatted and not broken.
- UTM Validation: Validate UTM parameters to ensure they are correctly formed and supported by the tracking system.
- Client Testing: Test emails across multiple email clients and devices to identify and mitigate rendering issues.
Marketer view
Email marketer from EmailGeeks Forum explains that some email clients will display a plain text version and not the HTML version. He advises to check the plain text version and make sure the links are not broken or wrapped in brackets.
25 Mar 2023 - EmailGeeks Forum
Marketer view
Email marketer from Marketing Over Coffee Podcast shares that UTM parameters are a common source of issues. Ensure UTM parameters are correctly formed, and avoid using characters not supported by the tracking system. Validate them after implementation.
5 Aug 2021 - Marketing Over Coffee Podcast
What the experts say
2 expert opinions
The addition of random characters to URLs in email click tracking is often due to encoding issues, HTML parsing differences across email clients, or coding inconsistencies. A specific email client might be consistently causing problems due to how it interprets the HTML or handles encoding. Proper testing across various clients, along with correct URL encoding, is crucial to prevent these issues.
Key opinions
- Client-Specific Issues: A consistent email client might be the source of the problem due to its unique rendering engine.
- Encoding Errors: Encoding issues can corrupt URLs, causing random characters to appear.
- HTML Parsing Differences: Email clients parse HTML differently, leading to variations in URL interpretation.
Key considerations
- Client Testing: Thoroughly test emails across multiple clients and devices to identify client-specific issues.
- Correct Encoding: Ensure URLs are properly encoded to prevent corruption by email clients.
- HTML Validation: Validate HTML code to ensure it's correctly formatted and doesn't introduce parsing errors.
Expert view
Expert from Word to the Wise explains that email clients can sometimes corrupt URLs due to encoding issues or the way they parse HTML. She advises testing across multiple email clients and devices to identify and mitigate these problems. Correct URL encoding is critical.
15 Aug 2024 - Word to the Wise
Expert view
Expert from Email Geeks suggests random ISPs, users and links points to a consistent client. The way it's coded might be frustrating a client. He also provides examples `<a href='https....">` or `<a href="......>`
7 Feb 2023 - Email Geeks
What the documentation says
3 technical articles
Random characters are added to URLs in email click tracking due to a combination of factors including URL rewriting features with aggressive encoding, differing HTML rendering by email clients, and URL length limitations. Services like SendGrid advise checking encoding settings, while Litmus emphasizes testing across various clients. Oracle Eloqua recommends keeping URLs concise and using URL shortening to avoid truncation.
Key findings
- URL Rewriting: URL rewriting features with aggressive encoding can introduce unexpected characters.
- Client Rendering: Email clients render HTML differently, causing variations in URL interpretation.
- URL Length Limits: URL length limitations can lead to truncation and corruption of links.
Key considerations
- Encoding Settings: Check encoding settings within email service platforms.
- Client Testing: Thoroughly test emails across different clients to ensure proper URL rendering.
- URL Conciseness: Keep URLs concise and consider using URL shortening services when necessary.
Technical article
Documentation from Oracle Eloqua details that URL length limitations can cause truncation or corruption, leading to unexpected characters or broken links. It advises keeping URLs concise and using URL shortening services when necessary.
19 Mar 2024 - Oracle Eloqua
Technical article
Documentation from Litmus explains email clients render HTML differently, leading to variations in how URLs are interpreted. Some clients might add or remove characters, especially with long URLs or those containing special characters. Litmus recommends thorough testing across various clients.
31 Jul 2022 - Litmus
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