What causes gibberish custom tags being added to contacts?
Michael Ko
Co-founder & CEO, Suped
Published 30 May 2025
Updated 17 Aug 2025
5 min read
Discovering gibberish custom tags appended to your contact records can be a frustrating and confusing experience. It's not just an aesthetic issue, but a red flag signaling deeper problems within your data management or inbound lead capture processes. These strange, often alphanumeric strings like xSHAREDPHOTODISPLAYPREFALWAYSASK or random keyboard smashing are rarely benign, indicating potential vulnerabilities that could impact your email deliverability, data hygiene, and overall contact management efficiency.
Many teams find themselves scratching their heads, wondering how these bizarre entries appear without manual intervention. It's a common issue that often points towards automated processes or external influences rather than human error.
Understanding the root causes is the first step toward implementing effective preventative measures and cleaning up your valuable contact database.
Understanding the source of gibberish tags
One of the most frequent culprits behind gibberish custom tags being added to your contacts is malicious or automated traffic. Bots are constantly scanning the internet for forms to fill out, often with random or pre-programmed data, including gibberish text in fields not specifically designed for email addresses.This leads to fake sign-ups and corrupted contact data.
Beyond bots, glitches in data synchronization between different platforms can also introduce unexpected characters. If your CRM, email service provider (ESP), or other marketing tools are not perfectly aligned, or if data is transferred via improperly encoded files, fields can become corrupted during the import or update process. For instance, sometimes custom labels on contacts might revert or be replaced by default or gibberish values if there's an underlying system conflict.
Another less common but possible cause is human error. While unlikely to generate truly random gibberish, impatient users might type placeholder text like asdf into required custom fields without realizing the implications for data hygiene. This highlights the need for clear instructions and robust field validation on all data input forms.
The silent threat to your data
Gibberish data contaminates your contact lists, making segmentation inaccurate and personalization efforts ineffective. It can lead to higher bounce rates if these 'contacts' are also associated with invalid email addresses, potentially landing your sending domain on a blocklist (or blacklist).
This can severely impact your email deliverability and sender reputation, pushing legitimate emails into the spam folder.
The broader impact on your email program
The presence of gibberish (or otherwise invalid) tags can severely impact your email marketing and overall business operations. For starters, it directly affects data quality, leading to inaccurate analytics and a skewed understanding of your audience. When your data is dirty, your ability to make informed decisions is compromised.
From an email deliverability standpoint, a contact list filled with bot-generated entries often includes invalid email addresses or even spam trap addresses. Sending to these can significantly damage your sender reputation, leading to lower inbox placement rates and potentially landing your domain on an email blocklist.
Furthermore, managing a contact database riddled with gibberish takes up valuable time and resources. Your team might spend hours manually cleaning up records, a task that diverts attention from more strategic marketing efforts. It's a drain on efficiency that can be largely avoided with proactive measures.
Problem: Uncontrolled data entry
Unrestricted forms and lack of validation allow bots and sometimes even impatient humans to inject meaningless data into custom fields.
Data quality degradation: Contaminated contact records lead to unreliable analytics and ineffective segmentation.
Increased bounce rates: Gibberish in email fields (or associated with invalid emails) results in hard bounces, harming sender reputation.
Solution: Robust validation & monitoring
Implementing stringent input validation and continuous monitoring helps filter out bad data before it enters your system.
Enhanced data hygiene: Keep your contact lists clean and reliable for accurate reporting and targeting.
Improved deliverability: Minimize invalid addresses and reduce the risk of hitting spam traps, protecting your sender reputation.
Preventative measures and data hygiene
To prevent gibberish custom tags from polluting your contact lists, proactive measures are essential. Start by securing your web forms, as these are often the primary entry points for automated attacks. Implementing CAPTCHAs, honeypots (hidden fields that bots often fill but legitimate users don't see), and client-side validation can significantly reduce bot submissions.
Beyond form security, enforce strict input validation for all custom fields. This means defining what kind of data is acceptable (e.g., alphanumeric, specific formats, character limits) and rejecting anything that doesn't conform. For instance, if a field is for a name, it shouldn't accept symbols or long strings of random characters. Your email service provider or CRM might have built-in validation options that you can configure.
Regular data auditing is also critical. Schedule periodic reviews of your contact database to identify and clean up any anomalous entries. This proactive approach helps maintain the integrity of your data over time and prevents issues from accumulating and becoming overwhelming. It's an ongoing process, not a one-time fix.
Example: JavaScript function for basic custom tag validationjavascript
function validateCustomTag(tag) {
const gibberishRegex = /^[a-zA-Z0-9!@#$%^&*()_+\-=\[\]{};':"\\|,.<>\/? ]*$/;
if (tag.length < 3 || tag.length > 50) { // Example: min 3, max 50 chars
return false; // Tag length outside acceptable range
}
if (!gibberishRegex.test(tag)) {
return false; // Contains invalid characters or patterns
}
// Add more specific checks if needed, e.g., if it matches known bot patterns
return true;
}
Attribution and ownership
Improving the attribution of your data sources is paramount. Knowing exactly where each contact and its associated tags originate allows you to pinpoint problematic channels. If a specific signup form or integration consistently generates gibberish tags, you'll know where to focus your efforts for remediation.
This involves working closely with your marketing, sales, and IT teams to ensure that all data ingestion points are properly configured and monitored. By seizing ownership of these processes, even if they were set up before your time, you empower yourself to implement the necessary controls and ensure data integrity going forward.
Views from the trenches
Best practices
Implement CAPTCHA or reCAPTCHA on all public-facing forms to deter bot submissions effectively.
Utilize honeypot fields in your web forms. These hidden fields are invisible to humans but are often filled by bots, allowing you to identify and block them.
Enforce strict server-side and client-side validation rules for all custom fields to ensure data adheres to expected formats and ranges.
Regularly audit your contact database for anomalies, duplicates, and gibberish entries to maintain data cleanliness.
Establish clear data attribution for every contact source so you can quickly identify and address problematic acquisition channels.
Common pitfalls
Relying solely on client-side validation which can be bypassed by sophisticated bots.
Neglecting to monitor form submission rates and patterns, missing early signs of bot attacks or data corruption.
Failing to implement a consistent data governance policy across all platforms and integrations.
Ignoring small instances of gibberish, allowing them to accumulate and degrade overall data quality over time.
Not training staff on proper data entry practices for custom fields, leading to inconsistent or junk data.
Expert tips
Consider using an external email validation service to proactively clean lists and prevent invalid emails from reaching your system.
For critical forms, implement multi-factor authentication or email verification steps to confirm user legitimacy.
Leverage DMARC, SPF, and DKIM to enhance email authentication, which indirectly helps deter spam and malicious inputs related to email interactions.
Automate data cleaning processes where possible, such as removing contacts with specific gibberish patterns or high bounce rates.
Collaborate with your IT and web development teams to secure all data entry points and integrate robust anti-bot measures at a foundational level.
Marketer view
Marketer from Email Geeks says understanding how contacts are normally added can help trace the source of the gibberish data.
2024-06-20 - Email Geeks
Marketer view
Marketer from Email Geeks says examining the pattern of the gibberish text is crucial for identifying its origin, such as bot-generated data.
2024-06-20 - Email Geeks
Conclusion: Securing your contact data
Gibberish custom tags added to your contacts are a clear indicator that your data integrity is at risk. By understanding that these anomalies often stem from bot activity, integration issues, or inadequate form validation, you can take targeted steps to address the problem at its source.
Implementing robust form security, rigorous data validation, and regular auditing will not only eliminate these gibberish entries but also bolster your overall email deliverability and data quality, ensuring your marketing efforts are built on a solid, clean foundation.