The main difference between Retarus and iFax Fax’s API is scalability and integration. iFax offers a more scalable and flexible API interface for cloud-based systems and applications. Meanwhile, the Retarus Fax API requires more in-depth knowledge about integrating fax into existing platforms.
Retarus and iFax Fax API Features Comparison
iFax vs Retarus | |||||
Price per page | HIPAA Compliance | Secure Fax Transmissions | Programmable API | High-Volume Faxing | |
iFax | 1¢ | Yes | Yes | Yes | Yes |
Retarus | Custom plans | Yes | Yes | Yes | Yes |

When comparing the API functionality of Retarus vs iFax, consider the following factors:
Pricing
For only $25 per month, the iFax Pro plan already provides you access to its programmable Fax API. You also get a free staging API key, which you can use to test how the integration works and whether it fits your business requirements. Plus, you gain access to advanced fax features such as smart folders, eSignatures, and sending faxes by email.
Meanwhile, the pricing for Retarus depends on your API needs. It follows a “pay-per-use” business model, so no plans are available with fixed monthly or yearly subscription rates.
Reliability
With iFax, you can count on its Fax API to be available 99.99% of the time. It ensures the deliverability of high-volume fax transmissions without frequent downtimes. It also lets you do performance testing to avoid potential bottlenecks once you incorporate specific fax functionalities into existing applications.
The same applies to Retarus. The cloud-based Fax API provider has extensive documentation and can continuously monitor the performance of API endpoints to ensure optimal operations.
Security
Securely send or receive faxes with iFax’s robust security and authentication measures. Every API call comes with a specific HTTP method to ensure unique authentication keys for added security. On top of that, all fax transmissions via API use 256-bit encryption to prevent unauthorized access.
As for Retarus, customer systems utilize TLS (Transport Layer Security) or optional Virtual Private Network (VPN) to the Retarus Enterprise Cloud. Retarus also applies different types of encryption, such as AES 256-bit, PGP, or X.509 per file type.
Compliance
One of the top features of iFax is its adherence to the highest federal and international standards, such as HIPAA and GLBA. It provides the necessary measures for covered entities to protect their sensitive documents containing protected health information (PHI) when using API to send and receive faxes. Our fax service will also sign a Business Associate Agreement (BAA) for HIPAA compliance at no added cost.
Similarly, Retarus is a HIPAA-compliant cloud fax solution that offers secure API services. It has advanced access controls and authentication codes to protect developer systems against unauthorized access.
Integration
With the iFax programmable API, users can seamlessly integrate their faxing capabilities into ERP, CRM, and cloud-based systems. It uses REST API to streamline communications and offer greater flexibility when sending and receiving fax documents.
Retarus, on the other hand, uses multiple data transfer protocols to integrate fax functionality into web and mobile applications. Currently, it supports REST and SOAP API, making online faxing more efficient without needing fax servers or modems.
Audit Trails
iFax automatically tracks fax history and verifies the delivery of each document transmitted through API. It makes tracking and monitoring faxes sent from ERP and EHR systems seamless and efficient, helping ensure compliance with various regulatory requirements.
Meanwhile, Retarus provides audit trails to track every failed or successful fax transmission. However, there’s no mention of whether it automatically logs faxes that go through API or other integrations.
Scalability
iFax via API provides scalability and integration with existing systems and applications. When writing API requests, you can use your preferred programming language and chosen framework to incorporate fax functionality into various workflows. Additionally, you can scale the volume of faxes sent and received without worrying about infrastructure limitations.
With the Retarus Fax API, you can easily manage high volumes of faxes while maintaining a smooth and efficient workflow. It offers high availability and high capacity, providing you with the exact bandwidth you need at any particular moment.
Retarus and iFax Comparison: Which Fax API Provider Is Good for You?
iFax vs Retarus? Using API to fax directly from existing software or systems means more freedom to accomplish tasks quickly and efficiently. Therefore, choosing a secure and reliable Fax API provider can give you a competitive edge.
With the iFax Fax API, you don’t need to learn about complex codes or hire a team of developers to build an entirely new faxing system. All you need is to integrate our service’s fax functionality into the app or software you’re currently using. Once set, you can fax documents seamlessly in the comfort of your existing workflow.
Experience a feature-rich API faxing solution.
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