# 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. --- ## What Our 98% Delivery Guarantee Covers ### Scope of Guarantee Our 98% delivery guarantee applies to emails verified through: - **[Email Verifier API](https://tomba.io/email-verifier)**: Real-time email verification service - **[Bulk Email Verification](https://tomba.io/bulks/email-verifier)**: 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 --- ## 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 --- ## 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 --- ## 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 --- ## 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 --- ## 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 --- ## 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 --- ## 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 --- ## 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 - Bulk processing endpoints - Custom field mapping #### Third-Party Integrations - CRM system connections - Email marketing platform sync - Data enrichment workflows - Automated list cleaning --- ## 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 --- ## Support and Contact Information ### Guarantee Support Team Specialized support for delivery guarantee issues: - **Email**: [info@tomba.io](mailto: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 --- ## 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. --- 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.