Duplicate Killer – Prevent Duplicate Form Submissions vs Contact Form to Any API

Duplicate Killer – Block Duplicate Form Submissions in WordPress. WooCommerce – Prevent Accidental Duplicate Orders Duplicate Killer also protects WooCommerce Classic Checkout from accidental duplicate orders. WooCommerce already disables the “Place order” button, but duplicate orders can still happen when: Checkout is slow Payment gateways lag or retry Customers refresh the page Multiple tabs are used Network requests are retried Duplicate Killer FREE adds lightweight server-side duplicate protection for WooCommerce Classic Checkout. If the same customer attempts to submit an identical order within 60 seconds, the duplicate is blocked and a validation message is shown. !!! No changes to your checkout design. No impact on performance. No additional configuration required. If your forms receive the same email address multiple times, fake leads, or repeated submissions, this plugin blocks them instantly. Choose which fields must be unique (email, phone, text) and block duplicate entries automatically — without changing your form design or user experience. Duplicate Killer works silently in the background and integrates seamlessly with popular WordPress form plugins and page builders. Cross-Form Duplicate Protection (PRO) Duplicate Killer PRO introduces Cross-Form Duplicate Protection. This feature allows duplicate detection across multiple forms on your website. For example, if a user submits the same email address in two different forms, Duplicate Killer PRO can detect the duplicate and block the second submission. This is useful when: – multiple contact forms exist across different pages – marketing forms collect the same email address – lead capture forms should only allow one submission per user – different form plugins are used on the same site This feature is available in Duplicate Killer PRO. Free: In the free version, duplicate protection can be enabled for one form per supported plugin. PRO: Duplicate Killer PRO enables multi-form protection with individual rules and messages per form. Supported Plugins Elementor Forms Contact Form 7 Formidable Forms WPForms Lite Forminator Ninja Forms Breakdance Page Builder Forms Key Features ✔ Prevent duplicate form submissions without CAPTCHA ✔ Works with existing forms – no changes required ✔ Prevent duplicate submissions by Email, Phone or Text fields ✔ Stop duplicate emails and repeated leads ✔ One global error message for all forms (Free version) ✔ Cross-Form Duplicate Protection (PRO) ✔ Detect duplicates across multiple forms ✔ Optional IP-based duplicate protection ✔ Store unique entries securely in your WordPress database ✔ Automatically store uploaded files from Contact Form 7 ✔ Lightweight, fast and easy to configure ✔ WooCommerce Classic Checkout duplicate protection ✔ Server-side fingerprint validation (Email + Cart + Total + Currency) ✔ Fixed 60-second protection window (FREE) ✔ Structured duplicate logging (ready for PRO analytics upgrade) ✔ No changes to checkout or form design Common use cases Prevent duplicate leads in contact and lead generation forms Keep CRM and email lists clean Block repeated event registrations with the same email Ninja Forms Prevent duplicate submissions by Email, Phone or Text fields Clean validation messages No form design changes required NEW: Formidable Forms Support Duplicate Killer now fully supports Formidable Forms and helps you stop duplicate form submissions in WordPress. You can prevent duplicate entries in Formidable Forms contact forms and advanced forms by enforcing unique fields such as email address, phone number, or text fields. This feature works with Formidable Forms native fields, requires no additional configuration. Does not affect form design or user experience. Elementor Forms Support Duplicate Killer fully supports Elementor Forms. You can prevent duplicate submissions in Elementor contact forms, lead forms and popups by enforcing unique values such as email or phone number. NEW in PRO version: Elementor Group Mode allows you to treat multiple forms with the same Form Name as one unified protected form — even if Elementor generates different form IDs internally. Plugin Integrations Contact Form 7 Limit submissions by Email, Phone or Text fields Custom validation message for duplicate entries Automatically store uploaded files locally Elementor Forms Prevent duplicate submissions on Elementor native forms Works with contact forms, lead forms and popups Seamless integration without modifying form structure Forminator Select unique fields (Email, Phone, Text) Warn users when a value has already been submitted WPForms Lite Prevent duplicate entries without changing form layout Clean and simple validation messages Breakdance Page Builder Forms Prevent duplicate submissions on Breakdance native forms IP-based validation for cleaner data Fully compatible with Breakdance UI Free vs Pro Free Version Protect one form (per supported plugin) Global duplicate protection rules (for the protected form) One global error message Global IP-based submission limits Unique entries per user (cookie-based) WooCommerce (FREE): – Protect Classic Checkout only – Fixed 60-second lock window – Basic duplicate detection – Stores structured logs for seamless upgrade to PRO analytics Duplicate Killer PRO Protect multiple forms Per-form duplicate protection rules Cross-Form Duplicate Protection (detect duplicates across different forms) Custom error message for each form Different IP limits per form Unique entries per user, configurable per form Designed for sites with multiple forms and different submission needs Duplicate Killer PRO is ideal for sites with multiple forms and different audiences. WooCommerce PRO adds: – Checkout Blocks (Store API) support – Configurable lock window (30–300 seconds) – Advanced fingerprint controls (phone, shipping, IP, customer ID) – Order linking (direct link to matching WooCommerce order) – Gateway breakdown (Stripe, PayPal, COD, etc.) – Trends dashboard (Last 24h, 7 days, 14 days) – CSV export for audits and support teams – Detailed analytics (top products, domains, checkout types, IPs) – Designed for real-world edge cases such as slow hosting, gateway retries, reverse proxies and unstable mobile networks. When to use Duplicate Killer Use this plugin if you receive repeated submissions with the same email, phone number or text values. If you only need basic spam protection, a CAPTCHA plugin may be enough. When should I use Duplicate Killer PRO? Use the PRO version if your site has multiple forms with different purposes — for example a contact form, a registration form and a newsletter signup — and each one needs different duplicate submission rules. Does FREE support WooCommerce Checkout Blocks? No. Checkout Blocks use a different system (Store API) and require the PRO version. What happens if I upgrade to PRO later? All WooCommerce duplicate logs stored in the FREE version are automatically used by PRO analytics. No database migration is required. Does this prevent payment gateway retries? FREE prevents accidental duplicate submissions on Classic Checkout. PRO adds enhanced idempotency handling and deeper gateway analytics.

Contact Form 7 to Any API lets you send form submissions directly to any CRM, Webhook, marketing platform or REST API with complete control over payloads, endpoints, headers and authentication. Built for developers, agencies, and technical teams who need flexible, secure WordPress API and Webhook integrations without extra middleware. All data stays private within WordPress until it’s successfully sent to your chosen API. Video Demo: Key Features Send CF7 Leads to Remote API’s such as CRM and other External API using POST/GET Create up to 5 API Connections Supports Simple & Fixed Format of JSON Supports Basic Auth Supports Bearer Auth API Logs Management with submitted data and API response Auto Delete Logs (purge logs older than configurable number of days) Email Notifications on API Failure Save Contact Form 7 form submitted data to the database Export Contact Form 7 Data in CSV, EXCEL, PDF, Print Single Or Multiple delete CF7 entries Conditional Field Support (Equals / Not Equals) File input supported – Uploaded file will convert into BASE64 and send to API Multisite Compatible WPML Compatible Predefined Tags support Send data to multiple API (PRO) Support Multi Level or Any Format of JSON (PRO) Send attachments to any API (PRO) Option to Choose when to send data to API – Before CF7 mail sent OR After mail sent (PRO) Multi File Upload Support (PRO) Compatible with Multiline files upload for contact form 7 Plugin (PRO) Option to choose Numerical Fields / Integer Fields (PRO) Option to choose Multiple File upload fields (PRO) Retry Failed API Logs (Auto and Manual Retry) (PRO) Bulk Retry failed API calls (PRO) Advanced Email Notifications on API Failure (PRO) Priority Support (PRO) Paid plugin customization support for JWT Token Integration with Any API (Contact us) Paid plugin customization support for OAuth 2.0 API Integration (Contact us) Paid Plugin customization support for any API (Contact us) WPForms to Any API Plugin – (Plugin for WPForm Users – Connect WPForm to Any API) Upgrade to PRO for Advanced Integrations Unlock advanced flexibility and full control with Contact Form 7 to Any API PRO Unlimited API Connections per site Multi-level / Any JSON Structure support Multiple File Upload Field Support Define Integer Fields – map numeric fields precisely Retry Failed API Logs – auto and manually retry any failed API call directly from the log screen Bulk Retry – re-send multiple failed API calls at once with a single click Advanced Email Notifications on API Failure – send failure alerts to multiple recipients Priority Support for faster assistance Price: $29.99/year Upgrade to PRO Optional OAuth 2.0 and JWT PRO Add-On For APIs that require advanced authorization, our PRO Add-On ($99.99) provides: OAuth 2.0 and JWT token authentication Automatic access/refresh token management JWT Token Integration with Any API Perfect for enterprise or expiring token setups Get the Add-On Set Your Own Header Request Parameters Define custom header parameters to match your integration requirements. Examples: Authorization: MY_API_KEY Authorization: Bearer xxxxxxx Authorization: Basic xxxxxxx Content-Type: application/json Basic and Bearer authentication can be configured directly in the header input fields. Supported CRMs and APIs Connect Contact Form 7 with 200+ CRM and marketing platforms: Twilio WhatsApp — Watch Video Brevo — Watch Video Mailcoach — Watch Video Pipeline CRM — Watch Video Mailchimp — Watch Video Mailbluster — Watch Video Zapier — Watch Video HubSpot CRM — Watch Video Salesforce CRM Pipedrive — Watch Video Freshsales — Watch Video Airtable — Watch Video Capsule — Watch Video EngageBay — Watch Video OnePage CRM Clio Grow — Watch Video Close CRM — Watch Video Systeme CRM — Watch Video Insightly CRM — Watch Video Twenty CRM — Watch Video Agile CRM — Watch Video Sage CRM Odoo CRM/ERP System Fluent CRM Lead Post API Virtuagym API Pilotsolution OS Ticket Samdock CRM Mikrowisp Bats CRM FRS Labs API Get Cobra by ArcaMax Network Worldfilia SingleOps GorillaDesk API Sembark API Superoffice CRM Flowdesk JobAdder Unlatch CRM Mail2many Workato Jetbrains / Intellij Space API Fincenfetch Lead Docket Agendor API Lead IM Israel Personio Kala CRM Israel Pixxicrm easybizy sell.do Events500 SendPulse CRM And many more Browse all integration guides: Blog | Video Tutorials Our Other Plugins WPForm to Any API WPForm to Any API is most powerful plugin to send WPForm data to any third party services. It can be use to send data to CRM Or any REST API. Easy to use and User friendly settings Support Contact Form 7 to Any API is developed and supported by IT Path Solutions. If you have questions or encounter issues, visit our Support Forum or contact [email protected]. Your feedback helps us improve and expand this plugin for the entire WordPress community. We also welcome: Bug and documentation reports Feature suggestions Translation contributions How You Can Support WordPress grows through community, and your help makes a difference. Report Bugs or Issues: Found a problem? Report it using the official guide. Fix or Suggest Docs Updates: Share corrections or suggestions on the Support Forum. Report Security Concerns: Follow the WordPress Security Reporting Guide. Suggest Features or Improvements: Have ideas? Submit them here. Contribute to Translations: Help translate the plugin on WordPress Translate. Explore our other plugins or visit WordPress Gems to check out what we do. License This plugin is licensed under the GNU General Public License v2 or later. https://www.gnu.org/licenses/gpl-2.0.html