Replace 3 Expensive APIs with
One Sub-Millisecond Firewall
Why pay $555/mo across legacy SMTP verifiers, separate anti-fraud services, and gated B2B enrichment? EmailScore bundles real-time deliverability, SHA-256 abuse fingerprinting, and lead classification into a single <0.3ms endpoint.
Developer
1,000 lookups / mo
Side projects, early MVPs, and local signup flow testing.
- ✓1,000 lookups every month
- ✓<0.3ms response latency
- ✓Full, Compact & Sparse formats
- ✓Shannon entropy & Markov bot math
- ✓Live DNS & MX verification
- ✓Rate limit: 5 req/sec
Starter
10,000 lookups / mo
Eliminate fake registrations, disposable bots, and user typos.
- ✓10,000 lookups / month
- ✓DomainLedger dynamic age probe
- ✓Zero-day burner detection
- ✓Typo recovery & suggestions
- ✓SHA-256 abuse fingerprinting
- ✓Soft overage: $5.00 / 1k
- ✓Rate limit: 25 req/sec
Growth
50,000 lookups / mo
Gate personal emails, route B2B enterprise leads, and stop bot signups.
- ✓50,000 lookups / month
- ✓B2B Classification (`is_business_email`)
- ✓Mail Vendor Intelligence (Workspace/M365)
- ✓Zstd, Brotli & Gzip compression
- ✓Multi-token team API keys
- ✓Soft overage: $4.00 / 1k
- ✓Rate limit: 100 req/sec
Scale
150,000 lookups / mo
For scaling consumer apps, marketplaces, and high-frequency signups.
- ✓150,000 lookups / month
- ✓High-concurrency burst buffer
- ✓Dedicated rate-limit capacity
- ✓99.9% Uptime SLA
- ✓Team dashboard & audit log
- ✓Soft overage: $3.00 / 1k
- ✓Rate limit: 250 req/sec
Enterprise
500,000+ lookups / mo
Multi-million monthly volumes, dedicated clusters, and on-premise VPC licenses.
- ✓500,000 to 10M+ checks / mo
- ✓99.99% Uptime Contractual SLA
- ✓Dedicated Shared Slack Channel
- ✓Net 30 Invoicing & custom MSA
- ✓Single-binary on-premise license
- ✓Soft overage: $2.00 / 1k
- ✓Rate limit: 1,000+ req/sec
Stop Paying the $555/mo Multi-Tool Tax
Modern registration forms typically chain three fragmented vendors together. That creates fragile latency waterfalls and triples your monthly SaaS bills.
Includes 50,000 checks (5x volume), native SHA-256 multi-accounting fingerprinting, B2B company vs free classification, typo auto-correction, and Zstd compression in a single round-trip.
- ✓Save $4,272 every year compared to multi-vendor stacks
- ✓5,000x faster response time without blocking user checkout
- ✓Single API key, zero vendor sync headaches
Credits That NEVER Expire. Period.
Tired of NeverBounce and Kickbox confiscating your unused credits after 12 months? Every EmailScore prepaid pack remains active permanently. Buy once, clean anytime.
- ✓ Never expires
- ✓ Full JSON security dossier
- ✓ 38% less than ZeroBounce
- ✓ Never expires
- ✓ Sub-millisecond speed
- ✓ Typo auto-recovery
- ✓ Never expires
- ✓ Save $250 vs ZeroBounce ($649)
- ✓ B2B Mailbox classification
- ✓ Never expires
- ✓ High-concurrency batch API
- ✓ Zero data retention option
- ✓ Never expires
- ✓ Save $700 vs ZeroBounce ($3,199)
- ✓ Dedicated support contact
Market Comparison Benchmark
See how EmailScore compares across performance, fraud detection, and pricing constraints against industry leaders.
| Capability | EmailScore | ZeroBounce | NeverBounce | Fingerprint / IPQS | Clearbit / Apollo |
|---|---|---|---|---|---|
| Evaluation Latency | <0.3ms | 1,500 – 3,500ms | 800 – 2,500ms | 200 – 500ms | 800 – 2,000ms |
| Real-Time Signup Firewall | ✓ Native (<1ms UX) | ✗ Too slow for UX | ✗ Too slow for UX | ✓ Yes (Device only) | ✗ Batch / Webhooks |
| Shannon Entropy ($H > 3.6$) | ✓ Built-in Bot Math | ✗ No (Misses PRNG) | ✗ No | ✗ No email entropy | ✗ No |
| Anti-Abuse SHA-256 Fingerprinting | ✓ Included | ✗ Not available | ✗ Not available | ✓ Core ($99-$699/mo) | ✗ Not available |
| B2B Business vs Free Provider | ✓ Included | ✗ Basic free-mail only | ✗ Basic free-mail only | ✗ No | ✓ Core ($4,284/yr min) |
| Inline Typo Auto-Recovery | ✓ Included | Paid Add-on | ✗ No | ✗ No | ✗ No |
| Wire Compression (Zstd / Brotli) | ✓ Zstd + Brotli + Gzip | Gzip only | Gzip only | Gzip only | Gzip only |
| Prepaid Credit Expiration | NEVER Expire | Never Expire | 12-Month Trap | Monthly Reset | Monthly Reset |
| Free Plan Volume | 1,000 / mo forever | 100 / mo | 10 / mo | 100 / mo | No free API tier |
Frequently Asked Questions
How is EmailScore able to respond in less than 0.3 milliseconds?
Unlike legacy verifiers that initiate slow, blocking TCP/SMTP socket handshakes against mail servers (taking 1.5 to 30 seconds and risking IP bans), EmailScore executes all Shannon entropy math, bigram Markov probability, typo recovery, and DomainLedger dynamic lookups in pure, memory-mapped Rust. Our distributed DNS resolver caches authoritative records with zero daemon overhead.
How do soft overages work? Will my registration form ever get blocked?
On paid subscription plans (Starter, Growth, Scale, Enterprise), your production signup flow will never experience 429 rate limit dropouts or sudden service cutoffs. If you experience a viral surge and exceed your plan quota, lookups seamlessly continue at your tier's transparent overage rate (e.g., $4.00 per 1,000 checks on Growth). Free tier accounts are capped at 1,000 monthly lookups.
Do Pay-As-You-Go credits really never expire?
Yes, guaranteed. When you purchase a Pay-As-You-Go credit pack (10k, 50k, 100k, 500k, or 1M), those credits belong to your account perpetually. We will never confiscate or void your unused credits after 12 months, unlike competitors such as NeverBounce and Kickbox.
Can I switch between monthly and annual billing or cancel anytime?
Yes. You can switch between monthly and annual billing (with a 20% discount) at any time from your account dashboard. Upgrades take effect immediately with prorated billing, and cancellations take effect at the end of the current billing cycle with zero penalties.
How does the SHA-256 anti-abuse fingerprint protect our trial compute?
Every EmailScore response computes an RFC-compliant, normalized canonical SHA-256 hash that unifies plus-addressing (e.g. `user+test1@gmail.com`), dot-aliasing (`u.s.e.r@gmail.com`), and Googlemail domains into an identical root fingerprint. This prevents malicious botfarms from claiming dozens of free trials with a single inbox.
Can we deploy EmailScore on-premise or within our private cloud?
Yes. Enterprise plans include an optional single-binary license that runs directly within your private AWS, GCP, Azure, or bare-metal infrastructure. Zero customer email data ever egresses your boundary, ensuring effortless SOC 2, HIPAA, and GDPR compliance.
Protect Your Signups in <0.3 Milliseconds
Start with 1,000 free monthly lookups. Test the API in minutes with our single curl command. No credit card required.