Understanding how Email Spam Score Works
Email spam scores are numerical ratings that indicate how likely your email is to be flagged as spam by email service providers (ESPs).
Think of it as a credit score for your emails – the lower the score, the better your chances of reaching the inbox instead of the spam folder.
However, to improve the user experience, on this free email spam checker the performance score is not based on the spam score, but on the performance of the email from 0 to 100.
Why Spam Scores Matter for Deliverability
Your spam score directly impacts your email marketing and backlink outreach success in several ways:
- Inbox Placement: Lower scores increase your chances of landing in the primary inbox rather than spam folders.
- Sender Reputation: Consistently sending emails with high spam scores can damage your domain reputation, affecting all future email campaigns.
- Engagement Rates: Even if your email reaches the inbox, spam-like characteristics can deter recipients from engaging with your content.
- ROI: Better deliverability means more eyes on your content, leading to higher conversion rates and better return on your email marketing investment.
12 Critical Factors That Impact Your Spam Score in 2025
Our spam email checker it's following 12 factors that mostly impact your spam score.
This has been based on the successful email campaigns of our clients these last months of 2025.
Content Structure Issues
Email filters have become increasingly sophisticated in analyzing content structure to identify potential spam.
Content structure isn't just about what you say – it's about how you present your message.
1. Word Frequency and Repetition
Excessive repetition of words or phrases is a classic spam indicator.
- Natural Language Patterns: Legitimate emails typically show natural language variation. When certain words appear too frequently, it often indicates automated or mass-produced content.
- Marketing Overemphasis: Repeating keywords like "buy now" or "free" multiple times is a common spammer tactic to create urgency.
- Content Quality: High word repetition often signals low-quality or poorly written content, which spam filters are trained to catch.
2. Capitalization Problems
The use of excessive capitalization is one of the oldest spam indicators that still matters today:
- Shouting Effect: ALL CAPS text is considered the digital equivalent of shouting, which legitimate businesses rarely do.
- Attention-Grabbing Tactics: Spammers historically used excessive caps to draw attention, making it a red flag for filters.
- Professional Appearance: Overuse of capitals appears unprofessional and can harm your brand's credibility.
3. Punctuation Patterns
Unusual punctuation patterns often indicate potential spam:
- Emotional Manipulation: Multiple exclamation marks (!!!) or question marks (???) are often used to create artificial excitement or urgency.
- Pattern Recognition: Spam filters look for patterns like "!?!?!" or "......" that are rare in legitimate business communication.
- Professional Standards: Excessive punctuation deviates from standard business writing practices.
4. Special Characters and Numbers
The use of special characters and numbers in certain patterns can trigger spam filters:
- Obfuscation Attempts: Spammers often use special characters to bypass filters (like "F₹EE" instead of "FREE").
- Phishing Indicators: Unusual character combinations can indicate attempts to mimic legitimate brands or hide suspicious content.
- Readability Issues: Excessive use of special characters and numbers can make content harder to read, which legitimate emails typically avoid.
Email Format Issues
Poor email formatting isn't just about aesthetics – it can significantly impact whether your email reaches the inbox.
Email service providers analyze formatting patterns to identify potential spam, as certain format characteristics are commonly associated with unwanted or automated messages.
5. RE/FWD in Subject Lines
Adding "RE:" or "FWD:" to subject lines when there's no actual reply or forward is a classic spam tactic:
- Trust Exploitation: Spammers use these prefixes to make emails appear like ongoing conversations, exploiting recipient trust
- False Familiarity: These prefixes suggest previous interaction when none exists
- Filter Training: Major email providers specifically look for misused RE/FWD patterns
- Engagement Impact: Recipients are becoming increasingly aware of this tactic, leading to lower open rates
6. Word Length Issues
Having multiple long words (10+ characters) close together often indicates problematic content:
- Natural Language: Regular communication rarely uses multiple long words in sequence
- Technical Jargon: Excessive use of long words often indicates technical spam or phishing attempts
- Readability Concerns: Dense clusters of long words make emails harder to read
- Language Pattern Analysis: Spam filters flag unusual word length patterns as potential indicators of generated content
7. Content Length Problems
Extremely short email content raises red flags:
- Lack of Context: Very short emails often lack sufficient context for legitimate business communication
- Phishing Patterns: Brief emails with links are common in phishing attempts
- Value Proposition: Short content suggests limited value or potential scam
- Engagement Metrics: Brief emails typically show poor engagement rates, affecting sender reputation
8. Text-to-HTML Ratio Issues
The balance between visible text and HTML code is crucial:
- Hidden Content: Low text-to-HTML ratios might indicate hidden spam content
- Image-Heavy Emails: Too much HTML often means over-reliance on images, a common spam tactic
- Code Bloat: Excessive HTML can signal poorly coded templates or suspicious content
- Mobile Compatibility: Poor ratios often lead to display issues on mobile devices
Structure and Layout
9. Paragraph Length
Poorly structured paragraphs can trigger spam filters and reduce readability:
- Content Readability: Both extremely short (1-2 words) and long (10+ lines) paragraphs are red flags
- Content Flow: Inconsistent paragraph lengths suggest automated content generation
- User Experience: Poor paragraph structure impacts scanning and comprehension
- Mobile Optimization: Extreme paragraph lengths create poor mobile experiences
10. Link Density
Excessive links are a major spam indicator:
- Spam Pattern: High link density is associated with affiliate spam and phishing
- Trust Signals: Too many links appear promotional rather than informational
- Click Tracking: Multiple tracking links can trigger spam filters
- User Safety: Email providers protect users from potentially harmful link clusters
Content Triggers
11. Spam Trigger Words
Certain words and phrases automatically increase spam scores:
- Each trigger word increases spam score
- Multiple triggers compound the effect
- Context matters but is hard for filters to determine
- Industry-specific terms may need special consideration
12. Urgency Language
Creating false urgency is a classic spam tactic:
Better Alternatives:
- Use genuine deadlines when applicable
- Focus on value rather than pressure
- Explain why timing matters
- Use soft urgency ("Available this week")
Frequently Asked Questions
Why are my outreach emails going to spam even though I'm not sending spam?
Even legitimate emails can trigger spam filters due to factors like sending patterns, email content, or poor domain reputation. The key is to follow email best practices and properly authenticate your domain with SPF, DKIM, and DMARC records.
What email spam score is considered 'safe' for outreach campaigns?
A spam score below 5 out of 10 is generally considered safe for outreach campaigns, with lower scores being better. Most email service providers use similar scoring systems to evaluate the likelihood of an email being spam.
How many follow-up emails can I send before risking my spam score?
Best practice is to limit follow-ups to 2-3 emails per prospect with at least 3-4 days between each follow-up. This approach maintains a natural sending pattern while maximizing response chances without triggering spam filters.
Do shared hosting IP addresses affect my email deliverability?
Yes, shared hosting IPs can negatively impact your deliverability since you're sharing an IP address with other companies that might have poor sending practices. Consider using a dedicated IP or a professional email service provider for your outreach campaigns.
How can I warm up a new email account for outreach campaigns?
Start by sending a few emails daily to engaged contacts (colleagues, friends) and gradually increase volume over 2-4 weeks while maintaining engagement. This builds a positive sending reputation with email providers before starting your actual outreach campaigns.
How can I check if my domain is blacklisted and what should I do about it?
Use tools like MXToolbox to check if your domain appears on any blacklists, and if found, follow each blacklist's specific removal process. Most blacklists have a removal request form where you can explain the steps you've taken to resolve any issues.