Overview

98% Delivery Guarantee - Email Verifier

Tomba.io provides an industry-leading 98% Delivery Guarantee for our Email Verifier service. When you verify email addresses through our advanced verification system, we guarantee that 98% of emails marked as "deliverable" will successfully reach their intended recipients.

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What Our 98% Delivery Guarantee Covers

Scope of Guarantee

Our 98% delivery guarantee applies to emails verified through:

• Email Verifier API: Real-time email verification service
• Bulk Email Verification: Large-scale email list cleaning
• Integrated Verification: Verification through our other services (Email Finder, Domain Search)
• Chrome Extension: Email verification through our browser extension

Verification Results Covered

The guarantee applies to emails with verification results of:

• deliverable: Email exists and can receive messages
• valid: Email passes all verification checks
• verified: Email confirmed through multiple validation methods

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Advanced Verification Technology

Multi-Layer Verification Process

1. Syntax and Format Validation

• RFC 5322 compliance checking
• Local and domain part validation
• International domain support
• Special character handling

2. Domain Verification

• DNS MX record validation
• Domain existence confirmation
• Mail server availability checking
• Domain reputation analysis

3. SMTP Verification

• Real-time SMTP handshake simulation
• Mailbox existence confirmation
• Catch-all detection
• Greylisting identification

4. Advanced Behavioral Analysis

• Email pattern recognition
• Historical delivery data analysis
• Spam trap detection
• Disposable email identification

Real-Time Processing

• Instant Results: Verification completed in under 2 seconds
• Live SMTP Testing: Real-time connection to mail servers
• Dynamic Updates: Results updated based on current server status
• Global Network: Verification from multiple geographic locations

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Verification Results and Confidence Levels

Primary Results

Deliverable (98% Guarantee Applies)

• Score Range: 85-100
• Meaning: Email exists and can receive messages
• Guarantee: 98% delivery success rate
• Recommendation: Safe to send

Undeliverable

• Score Range: 0-25
• Meaning: Email doesn't exist or will bounce
• Action: Remove from lists immediately
• Accuracy: 99.9% bounce prediction

Risky

• Score Range: 26-84
• Meaning: Email exists but may have delivery issues
• Recommendation: Proceed with caution
• Common Issues: Catch-all, role-based, or filtered emails

Unknown

• Score Range: Variable
• Meaning: Cannot determine deliverability
• Causes: Server timeouts, greylisting, or restrictions
• Action: Manual review recommended

Enhanced Result Details

Detailed Attributes

• Gibberish Detection: Identifies nonsensical email addresses
• Disposable Email Detection: Flags temporary email services
• Role-Based Detection: Identifies generic addresses (info@, admin@)
• Webmail Detection: Distinguishes personal vs. business emails

Risk Indicators

• Spam Trap Risk: Probability of being a spam trap
• Catch-All Status: Whether domain accepts all emails
• Mailbox Full: Detection of full mailboxes
• Accept-All: Domains that appear to accept everything

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Guarantee Terms and Conditions

Eligibility Requirements

Qualifying Verification

• Emails verified through official Tomba.io services
• Results marked as "deliverable" with scores 85+
• Verification completed within the last 30 days
• Proper sending practices followed

Sending Requirements

• Use authenticated sending domains (SPF, DKIM, DMARC)
• Maintain good sender reputation
• Follow email marketing best practices
• Comply with anti-spam regulations

Measurement Standards

Success Criteria

• Primary Metric: Email successfully delivered to inbox
• SMTP Success: 250 OK response from receiving server
• No Hard Bounces: No permanent delivery failures
• Inbox Placement: Message reaches primary inbox folder

Exclusions from Guarantee

• Soft Bounces: Temporary delivery issues (full mailbox, server down)
• Content Filtering: Emails blocked due to content or sender reputation
• Recipient Filtering: User-defined rules or personal blocking
• Rate Limiting: ISP throttling or temporary restrictions

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Quality Assurance Measures

Continuous Monitoring

Real-Time Quality Checks

• Live SMTP server monitoring
• Continuous accuracy validation
• Performance metric tracking
• False positive detection

Historical Analysis

• Delivery outcome tracking
• Accuracy improvement algorithms
• Pattern recognition updates
• Machine learning optimization

Global Infrastructure

Distributed Verification Network

• Multiple verification points worldwide
• Redundant SMTP testing
• Load balancing and failover
• Regional optimization

Server Partnerships

• Direct relationships with major ISPs
• Trusted sender status
• Whitelist maintenance
• Delivery feedback loops

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Claim Process for Guarantee

Claim Eligibility

When to Submit a Claim

• Delivery rate below 98% for verified emails
• Systematic hard bounces on "deliverable" emails
• Consistent verification inaccuracies
• Pattern of false positives

Required Metrics

• Minimum of 100 verified emails for statistical significance
• Verification must be completed within 30 days
• Proper sending authentication required
• Detailed delivery logs necessary

Documentation Requirements

Verification Records

• Complete list of verified emails with scores
• Tomba.io verification timestamps and results
• Original verification confidence scores
• Batch processing records if applicable

Delivery Evidence

• SMTP delivery logs and bounce messages
• Email service provider delivery reports
• Bounce categorization (hard vs. soft)
• Timeline of sending attempts

Technical Information

• Sending domain authentication records
• Sender reputation scores
• Email content and headers (if relevant)
• ISP feedback and block notifications

Claim Resolution Process

Step 1: Initial Review (1-2 Business Days)

• Verification of claim eligibility
• Documentation completeness check
• Preliminary analysis of delivery patterns
• Assignment to specialist team

Step 2: Technical Analysis (3-5 Business Days)

• Detailed review of verification accuracy
• SMTP log analysis
• Cross-reference with our quality metrics
• Investigation of delivery failures

Step 3: Resolution (2-3 Business Days)

• Determination of guarantee applicability
• Calculation of service credits or remedies
• Implementation of account improvements
• Communication of results and next steps

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Remedies and Compensation

Service Credit Structure

Credit Calculation

• Standard Rate: 2x credits for each failed verification
• Premium Accounts: 3x credits plus additional services
• Enterprise Clients: Custom compensation packages
• Bulk Users: Volume-based credit adjustments

Credit Application

• Automatic application to account balance
• Can be used for any Tomba.io services
• No expiration date on guarantee credits
• Transferable between team members

Enhanced Services

Priority Re-verification

• Free re-verification of problematic emails
• Enhanced verification algorithms applied
• Priority processing queue access
• Dedicated account specialist support

Account Optimization

• Personal consultation with verification experts
• Custom verification rule development
• Integration optimization assistance
• Advanced feature access

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Optimization Best Practices

Pre-Verification Preparation

Email List Hygiene

• Remove obvious invalid formats
• Clean duplicates and variations
• Segment by source and age
• Prioritize high-value contacts

Batch Processing

• Optimal batch sizes (500-1000 emails)
• Appropriate timing intervals
• Monitor processing status
• Handle API rate limits properly

Post-Verification Actions

Result Segmentation

• High Confidence (95-100): Priority sending
• Good Confidence (85-94): Standard campaigns
• Lower Confidence (Below 85): Additional verification or exclusion
• Special Cases: Manual review for important contacts

List Maintenance

• Regular re-verification (quarterly recommended)
• Monitor bounce rates continuously
• Update verification status based on delivery outcomes
• Maintain suppression lists for hard bounces

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Advanced Features for Higher Accuracy

Enhanced Verification Options

Deep SMTP Analysis

• Multi-step SMTP conversation simulation
• Advanced server response interpretation
• Custom timeout configurations
• Retry logic optimization

AI-Powered Predictions

• Machine learning delivery predictions
• Historical pattern analysis
• Behavioral modeling
• Risk assessment algorithms

Integration Capabilities

Real-Time API

• Instant verification results
• Webhook notifications
• Bulk processing endpoints
• Custom field mapping

Third-Party Integrations

• CRM system connections
• Email marketing platform sync
• Data enrichment workflows
• Automated list cleaning

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Monitoring and Analytics

Performance Dashboard

Access comprehensive analytics through your Tomba.io dashboard:

• Verification Accuracy Tracking: Real-time accuracy metrics
• Delivery Rate Monitoring: Track guarantee compliance
• Historical Performance: Long-term accuracy trends
• Comparative Analysis: Benchmark against industry standards

Automated Alerts

• Accuracy Threshold Alerts: Notifications when accuracy drops
• Volume Processing Updates: Status of large batch verifications
• System Status Notifications: Service availability updates
• Guarantee Performance Reports: Monthly guarantee compliance summaries

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Support and Contact Information

Guarantee Support Team

Specialized support for delivery guarantee issues:

• Email: info@tomba.io
• Priority Support: Available for guarantee-related issues
• Technical Consultation: Expert advice on verification optimization
• Account Management: Dedicated support for enterprise clients

Response Time Commitments

• Guarantee Claims: Response within 24 hours
• Technical Issues: Response within 4 hours
• General Inquiries: Response within 2 hours during business hours
• Emergency Support: Available 24/7 for critical issues

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Frequently Asked Questions

Q: How does the 98% guarantee compare to the 95% Email Finder guarantee?

A: The Email Verifier has a higher guarantee (98%) because it performs additional real-time validation checks on existing emails, while Email Finder discovers new emails which inherently carry slightly more uncertainty.

Q: What's the minimum number of verifications needed to claim the guarantee?

A: We require a minimum of 100 verified emails marked as "deliverable" to ensure statistical significance for guarantee claims.

Q: How often should I re-verify email addresses?

A: We recommend re-verification every 3-6 months for active lists, or immediately before important campaigns, to maintain the highest accuracy.

Q: Do verification results expire?

A: Verification results remain valid for 30 days under our guarantee. After that, email deliverability may change due to factors outside our control.

Q: Can I get a refund instead of service credits?

A: Our standard remedy is service credits, but enterprise clients may have different arrangements based on their service agreements.

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Our 98% Delivery Guarantee for Email Verifier represents the highest standard in email verification accuracy, backed by advanced technology and our commitment to your success.