Frequently Asked Questions

DQVerify is a US data validation platform that verifies postal addresses, email addresses, and phone numbers through a single integration — one API key, one endpoint, one unified JSON response.

Unlike traditional validation vendors that require procurement cycles, SFTP file transfers, and enterprise contracts, DQVerify is fully self-serve: sign up with a business email, receive 100 free validations, and start immediately — no credit card, no sales call.

• Address validation — USPS CASS-certified standardization and DPV deliverability confirmation
• Email validation — live SMTP handshake, MX record check, and disposable domain detection
• Phone validation — real-time carrier lookup and line-type identification (mobile / landline)

API response time is under 150ms at the 95th percentile, with a 99.99% uptime target.

DQVerify validates three types of contact data through a single integration. Each module is billed separately at one credit per call.

• Address — standardizes to USPS format, confirms deliverability via DPV, appends ZIP+4, county, and RDI (Residential Delivery Indicator)
• Email — MX record lookup, live SMTP handshake, disposable domain and spam trap check; returns a Low / Medium / High risk score
• Phone — identifies carrier, classifies line type (mobile or landline), confirms active/ported status

Submitting all three in one API call costs 3 credits (one per module), but requires only one API key and one integration.

Yes. DQVerify is powered by USPS CASS (Coding Accuracy Support System) certified software through a licensed OEM partnership.

CASS certification applies to batch CSV processing jobs — meaning batch output qualifies for USPS compliance programs such as nonprofit postal discounts.

Individual real-time API calls return USPS DPV (Delivery Point Validation) confirmation — the same deliverability check — but are not independently CASS-certified per USPS program definitions.

Beyond the core address, email, and phone modules, DQVerify offers supplementary data services available on Verify and Enterprise plans:

• Email activity scoring — identifies whether an address has been recently active, reducing false positives beyond deliverability
• B2B enrichment — appends company, industry, and firmographic data to validated business contacts
• Mooved detection — flags contacts who have recently changed address, enabling proactive record updates
• ID Check — validates identity against partner databases for KYC and onboarding workflows
• Geolocation — appends latitude, longitude, and county data to validated addresses

Contact the team for specifics on any module.

DQVerify Standalone is the web-based platform version of DQVerify — no API integration, no code, no SFTP required. It supports two modes:

• Real-time validation — enter a single address, email, or phone record and get an instant validated result in the browser
• Batch validation — upload a CSV or spreadsheet, point your columns to the correct fields using a flexible mapping interface (no rigid column format required), and download an enriched output file

DQVerify connects directly to your data wherever it lives — cloud platforms like AWS or Azure, data warehouses like Snowflake, or a simple CSV upload. No data migration required. Available on Verify and Enterprise plans.

Yes — DQVerify's key differentiator is one integration, not one shared credit. A single POST to /validate can include an address, an email, and a phone number, and DQVerify returns results for all three in one JSON response, typically under 150ms.

Each module is billed separately (1 credit per address, 1 credit per email, 1 credit per phone), but you only need one API key — replacing the typical stack of:

• Address validation — Smarty or Melissa (separate key + billing)
• Email validation — ZeroBounce or NeverBounce (separate key + billing)
• Phone validation — Twilio Lookup or Numverify (separate key + billing)

DQVerify email validation runs a multi-step sequence:

• MX record check — confirms the domain is configured to receive email
• Live SMTP handshake — tests whether the specific address is accepted by the receiving mail server without delivering a message
• Reputation check — cross-references disposable providers (e.g. Mailinator), role-based prefixes (admin@, noreply@), and known spam trap addresses

The result is a risk score (Low / Medium / High) plus structured error codes for routing logic:

• 00 — valid
• 01 — valid but username unconfirmed
• 02 — address not found in domain
• 03 — inbox full
• 04 — empty
• 91 — syntax error
• 92 — non-existent domain
• 93 — blacklisted domain
• 94 — reserved or role-based name
• 95 — disposable email
• 96 — IP blocked
• 99 — domain not responding

A validated address response includes:

• Standardized address in USPS format (all-caps, abbreviated directionals and street suffixes)
• ZIP+4 code (if the address is deliverable)
• DPV status — deliverable, vacant, or non-delivery point
• County name and FIPS code
• RDI flag — residential or commercial
• Standardized unit/secondary address component (if provided)

For undeliverable inputs, DQVerify returns a structured error code explaining why — street not found, city/state/ZIP mismatch, missing unit number, etc. The response schema is consistent across all outcomes.

Yes. DQVerify supports address validation across 240+ countries and territories using the same API key and /validate endpoint.

• UK — Royal Mail PAF standard
• Europe — national postal authority databases
• Asia-Pacific and Latin America — regional postal standards

US addresses carry USPS CASS certification. International addresses are validated against licensed postal authority datasets — CASS is a US-only standard and does not apply to international lookups.

Smarty validates addresses only. DQVerify validates addresses, emails, and phone numbers through a single integration — one API key replaces 2–3 vendors.

On address validation specifically, both platforms deliver:

• USPS DPV confirmation
• ZIP+4 appending
• County data
• 240+ countries for international addresses

DQVerify additionally returns RDI (Residential Delivery Indicator) and structured validation flags. Migration from Smarty is typically a one-line base URL swap — DQVerify's address endpoint accepts the same input fields as Smarty's US Street Address API.

From sign-up to first validated record in under five minutes:

• 1. Create a free account with a business email or Google SSO — no credit card required. You receive 100 free validations immediately.
• 2. Copy your API key from the dashboard.
• 3. Send a POST request to /validate with any combination of address, email, and phone fields. Working code snippets for curl, Python, Node.js, and PHP are provided in the dashboard.

The API uses standard JSON bodies, standard HTTP status codes, and a consistent response schema across all three validation types.

Yes — DQVerify connects directly to your data wherever it lives, with no code or SFTP setup required:

• CSV or spreadsheet upload — map your columns using a drag-and-drop interface and download an enriched output file
• Cloud connectors — connect directly to data stored on AWS, Azure, Google Cloud, or warehouses like Snowflake
• Files under 50,000 rows typically complete in under ten minutes
• Larger files process asynchronously and deliver results via webhook or dashboard link

Batch output runs through DQVerify's CASS-certified address validation engine, so it qualifies for USPS compliance programs. Available on Verify and Enterprise plans.

DQVerify offers three tiers — no monthly subscription on any plan. Every tier uses the same API, the same response format, and the same validation engine. The only difference is volume and support level.

• Validate (free) — 100 credits at signup, no credit card required. Use all three validation types (address, email, phone) to evaluate DQVerify on your own data before committing.
• Verify — one-time credit purchase starting at $700 for 20,000 credits, with volume tiers up to 500,000. Pricing varies by module because each draws on different licensed data sources (USPS postal data, SMTP infrastructure, carrier networks). Credits are valid for 1 year from purchase — no monthly renewal, no auto-charge.
• Enterprise — for organizations needing CRM connectors (Salesforce, Shopify), volumes above 500,000, or compliance features like dedicated SLAs and ISO 27001 certification. Custom pricing based on volume and module mix — contact the team for a quote.

Each module draws on a different licensed data source with its own cost structure, and DQVerify passes that difference through transparently rather than hiding it in a blended rate:

• Address — USPS CASS-certified data licensed via a federally regulated dataset. US address validation uses DPV confirmation, ZIP+4 appending, and county enrichment from the USPS postal authority database.
• Email — live SMTP infrastructure and continuously updated disposable-domain and spam-trap databases. Every validation opens a real-time connection to the recipient's mail server, which carries operational cost per lookup.
• Phone — real-time carrier network lookups for line-type identification (mobile, landline, VoIP). Carrier data is sourced from licensed telecom databases that charge per query.

Per-module pricing means you only pay for the validation types you actually use. If your workflow only needs email validation, you are not subsidizing address or phone lookups. The pricing calculator on the pricing page shows exact per-credit costs by module and volume tier.

Paid credits (Verify plan packs and pay-as-you-go top-ups) are valid for 1 year from the date of purchase. Credits are consumed as you use them — your balance carries forward and does not reset monthly. There is no auto-renewal and no recurring charge; when your credits run low, you purchase another pack at whatever volume tier fits your current needs.

The 100 free credits included at signup are valid for the 14-day free trial and expire at the end of the trial or when you upgrade to a paid plan, whichever comes first. Free credits work identically to paid credits — same API, same validation quality, same response format — so your evaluation results are representative of production performance.

If you need to check your remaining balance, the DQVerify dashboard shows real-time credit usage broken down by module (address, email, phone) and by time period.

DQVerify is one platform for all three validation types — one API key, one endpoint, one unified JSON response. Billing is per module per call, so you only pay for the validations you actually run:

• 1 credit per address lookup — includes USPS standardization, DPV deliverability confirmation, ZIP+4, county, and RDI enrichment
• 1 credit per email check — includes MX record lookup, live SMTP handshake, disposable domain detection, and risk scoring
• 1 credit per phone lookup — includes carrier identification, line type classification, and active/ported status

Submitting all three in one request costs 3 credits (one per module). Your credit balance is shared across all modules — there are no siloed pools, so you can shift your usage mix without buying separate packs. The practical advantage is replacing 2–3 vendor integrations (typically Smarty for addresses, ZeroBounce for emails, Twilio Lookup for phones) with a single API key, a single billing account, and a single response schema.

Enterprise is designed for organizations with high-volume needs (500,000+ validations per year), CRM connector requirements, or compliance demands that go beyond the self-serve Verify plan. It uses the same validation engine and API as every other tier — the difference is support, integrations, and contractual guarantees:

• Native CRM connectors — pre-built integrations for Salesforce, Shopify, and other platforms that validate records directly inside your existing workflows without custom API development
• Dedicated Customer Success Manager — a named contact who handles onboarding, monitors your usage patterns, and helps optimize your validation strategy across modules
• Custom SLA and uptime guarantees — contractual commitments beyond the standard 99.99% uptime, including response time SLAs for support tickets
• Volume-tiered pricing — per-credit costs decrease at higher volume commitments, with pricing customized to your specific module mix and annual volume

Enterprise is not unlimited — it is priced based on volume and connector scope. Contact the team at support@dqverify.com to discuss your requirements and receive a custom quote.

DQVerify runs on two layers, and neither one keeps your validation data:

• The website, customer portal and account systems are hosted on Google Cloud in the United States (us-central1).
• Validation itself (address, email and phone checks) is performed by our affiliate DQE Software SAS on infrastructure in the European Union (France). Inputs travel over encrypted connections, are processed in real time, and are not retained once your request completes.
• Batch results are available for download during your session and are then deleted, whether or not you download them. Download your results before you leave the page.

DQE Software SAS, which develops and operates the validation technology, holds ISO/IEC 27001:2022 certification (BSI certificate IS 845668). DQVerify's Privacy Policy (effective September 16, 2026) describes what we collect, where it is processed, how long it is kept, and how to make a privacy request.