Zamzar API

Zamzar API is a cloud REST service for developers adding file conversion to a mobile, web, or desktop application. It is best for products that need many file formats and flexible input sources, rather than teams seeking a general-purpose file host. The free test access is useful for evaluation, while production fit depends on credit demand, file sizes, and retrieving converted files through the API.

Overview

With more than 1,100 conversions spanning documents, video, images, audio, eBooks, CAD, 3D, and compressed files, Zamzar offers broad coverage for applications that encounter varied file types. It accepts files from a user's machine and files reachable through HTTP, FTP, SFTP, or Amazon S3. That flexibility can suit services with existing storage workflows, and Zamzar says its cloud service can scale from one file to 10,000. Scaling capacity does not remove the practical limits imposed by plan credits and file-size caps.

This is a conversion API, not a delivery layer: converted files should be downloaded through the API, and the service is not intended to act as a CDN. That distinction matters for products that need persistent public file distribution. PDF conversion and data extraction are supported, and deployment is cloud-based.

Key features

Developer integration

Official SDKs for Java, PHP, and Python give teams in those languages a direct starting point; code samples for C#, cURL, Node.js, and other languages broaden the options for other stacks. The REST-based HTTP interface is the core integration surface. Amazon S3, FTP/SFTP, and HTTP/HTTPS are also listed as supported integrations, which can reduce the need to route files through a separate upload path.

Testing, security, and support

A Test account requires no credit card, and sandbox mode lets every account run conversion jobs without charge, subject to file-size and job-count limits. This is a sensible way to validate basic integration before committing to a paid plan, though the Test plan's 1 MB file ceiling is too restrictive to stand in for production-scale evaluation.

Zamzar describes safeguards including TLS traffic protection, salted and hashed API passwords, firewalls, access controls, regular patching, and monthly external security scans. It says it meets GDPR, UK GDPR, and Data Protection Act 2018 responsibilities and is registered with the UK Information Commissioner's Office. Support response targets vary by plan from one to three days, and the company says its support team is staffed by software developers.

Pricing

The freemium structure starts with a small no-cost Test plan and scales by monthly credits, file size, storage period, and support response time. Successful conversions cost at least one credit; the first 50 MB of input is included in the conversion cost, and unused monthly credits do not roll over. Budgeting should account for both the monthly allowance and overage charges.

Plan	Price	Included and limits
Test	free	100 credits; 1 MB maximum file size; files stored 1 day; support response 3 days; no overages; no card required.
Startup	$25 a month	500 credits/month at $0.05 per credit; $0.05/credit overages; 50 MB maximum file size; files stored 2 days; support response 2 days.
Growth	$99 a month	2,500 credits/month at $0.04 per credit; $0.04/credit overages; unlimited maximum file size; files stored 3 days; support response 2 days.
Scale	$299 a month	10,000 credits/month at $0.03 per credit; $0.03/credit overages; unlimited maximum file size; files stored 3 days; support response 1 day; custom conversions.

Startup is the entry point for modest production volume, but the 50 MB ceiling and 500-credit allowance may constrain larger or busier workflows. Growth removes the maximum file-size cap and increases the allowance substantially, making it a better fit for heavier use. Scale lowers the per-credit rate and adds custom conversions, with a faster stated support response; it is aimed at high-volume integrations. On all paid plans, unused monthly credits expire rather than carrying forward.

Platforms

Zamzar API is categorized for Android, iOS, Linux, macOS, web, and Windows, with the API itself serving as the cloud integration point across application types. The platform labels do not change the central requirement: applications must implement the API and retrieve converted files through it.

Who it's for

This is a strong candidate for developers building a product or service that needs conversions across multiple file families, accepts files from varied sources, and can manage usage as credits. The test account and sandbox are useful for integration work, while the paid tiers provide a path from modest monthly volume to larger workloads. It is less suitable when the main requirement is CDN-style hosting, when a workflow must handle files above Startup's 50 MB limit on a lower paid tier, or when predictable costs depend on unused credits rolling over.

Pros and cons

• Pros: More than 1,100 conversions across a wide range of file categories make it useful for applications with mixed file workflows.
• Pros: Local, HTTP, FTP, SFTP, and S3 input options accommodate several common ways to supply files.
• Pros: Official Java, PHP, and Python SDKs, plus samples for other languages, provide multiple integration starting points.
• Pros: A no-card Test account and free sandbox mode allow initial evaluation without a paid commitment.
• Cons: The Test plan's 1 MB file limit and job restrictions make it unsuitable for realistic testing of larger files.
• Cons: Credits are charged per successful conversion, unused monthly credits expire, and overages are billed per credit.
• Cons: Startup caps files at 50 MB, while converted files must be retrieved through the API rather than treated as CDN-hosted content.

Alternatives

For image-focused conversion, Aspose.Imaging is worth comparing: it has a free browser app capped at 10 files per operation, alongside freemium pricing and support across browser and several desktop and mobile platforms. FreeConvert GIF Maker is a more focused option for GIF-making workflows, with a free tier of 20 conversion minutes per day, a five-minute per-file limit, and up to 20 files per day.

Convertio is another freemium conversion service, with a Lite plan at $11.99 a month that includes a 1 GB maximum file size and 1,000 monthly conversion credits; it may suit readers whose priority is that stated file-size allowance. For local image processing, XnConvert offers free use for private, educational, and nonprofit purposes, while Converseen is free software under GNU GPL version 3 for Linux, macOS, and Windows.

Readers who prefer image-processing libraries can consider libvips, free under LGPL-2.1-or-later, or Pillow, open-source software with optional commercial support and maintenance through Sonar Subscription. GraphicsMagick is a free alternative for image processing that supports reading, writing, and manipulating images in over 92 major formats. These options are image-oriented or local tools rather than direct substitutes for Zamzar's broad hosted conversion API.

Compare more options in Image Converter Software, File Conversion Software, and PDF API Software.

Verdict

Zamzar API is best for developers who need broad conversion coverage, multiple file-source options, and a cloud service that can scale with demand. Its no-card test access and language SDKs lower the barrier to evaluation and integration. Choose it when conversion is a core workflow and credit-based usage is manageable; look elsewhere if you need CDN-style file delivery, rollover credits, or a lower-cost plan with a larger stated file-size limit.