Sharing Made Easy

Your business grows faster when it's easy for your users to tell their friends about you.

Making your users type or copy/paste their friends' email addresses discourages sharing because it's so much work.

Your Form

Simple form

5 minutes later...

Your Form withLogo

Cloudsponge form

Why choose CloudSponge?

Our widget will let your users input their friends' email addresses into your "refer a friend" form without typing anything.

CloudSponge integrates with the most popular webmail services including Yahoo, Hotmail and Gmail and desktop address books such as Outlook and Mac OS X Address Book.

Our API gives you full control over every pixel of the user experience if our widget isn't right for you or if you're building a "find your friends" feature to help your users make connections on your website.

The options are endless, you can use your user's contacts however you like.

Single Access Point

Integrate once and get access to all of our supported address book sources rather than connecting to each one individually.

OAuth User Consent

We use OAuth User Consent APIs whenever they're available because your users don't want to share their important passwords with anyone.

Domain Knowledge Experts

We make sure your contact importer keeps working when third parties make changes.


Reliable, auto-scaled service means that you don't have to worry about uptime or scaling.

Plug CloudSponge into your website
in 3 easy steps


Create a CloudSponge account


Paste our code into your site


Grow faster!

What are people saying about us?

"Integrating CloudSponge was a snap. It makes it easy for our users to invite their friends and family to join Kiva, and to send them Kiva Cards ..."

Paul ericksen

Paul Ericksen
Senior Software Engineer

"... We picked CloudSponge because of the features they offer coupled with their robust SDKs and support, and have found the service very reliable ..."

Tim cederman haysom

Tim Cederman-Haysom
Director of Product

"... Since implementing CloudSponge ... more customers get through the process of sending an eCard ..."

Mike bracco

Mike Bracco
Product Manager

"... CloudSponge has been doing an excellent job for us. The team has been extremely helpful and responsive to our needs."

Andy hao

Andy Hao
Chief Technology Officer

"We are excited about what CloudSponge will be able to do for us as we transition away from Plaxo ..."

Kevin diamond

Kevin Diamond
Chief Technology Officer

"It literally took us 10 minutes to integrate with CloudSponge and doubled the number of invitations sent by our customers."

Dafeng guo

Dafeng Guo

Sign up and accelerate your growth!

It'll only take a few minutes to set up.

About the Free Accounts

If you're only using development-only domains (like localhost,, dev.*, staging.*, *.local or anything without a TLD) we won't ask you for a credit card number or try to bill you. Ever.