The best Unified API picks for CRM Integrations, Commerce, Open-Source, and more.
By Fabian Frank, Head of Product | Posted in Integrations, SaaS Tools, API Strategy
Unified APIs are changing the way SaaS products connect with external systems. Instead of building and maintaining dozens of separate integrations (like an embedded iPaaS solution would), a Unified API lets your engineering team build once and unlock connectivity across an entire category — like CRMs, HRIS, or accounting tools — through a single schema.
If you’re looking to scale quickly to a whole market category and avoid the maintenance nightmare of many fragmented integrations, Unified APIs are the way to go. But choosing the right one can still be tricky — everyone seems to claim to do everything.
The recently published Buyer's Guide to Integration Solutions from Filter Advisors, a technology consulting firm who has worked with many of these providers, offers a clear view of the market, ranking top Unified API providers by their specialization, pricing, implementation support, and CRM depth.
Below, we’ve summarized the standout options in the Unified API space to help you find the right option for you.
If you’re connecting to CRMs, Grid Squid is the obvious winner. The guide highlights it as the most specialized Unified API for CRM connectivity, with support for:
💰 Flat-rate pricing at $8.2k/month or $80k/year — no per-connection or per-API-call costs.
🧰 Built by developers, for developers, with clean schema design and an open API reference.
📞 Dedicated Slack channel and hands-on onboarding included.
“Best-in-class for CRM-centric SaaS; deep expertise and depth of functionality.” — Filter Advisors, 2025 Buyer's Guide to Integration Solutions and Software Connectors
Merge is one of the more well-known names in the Unified API space, and it offers:
🧾 Pricing starts free for a few linked accounts, with production plans from $650/month and up.
✅ Best for teams who need broad integration coverage and good observability tooling.
However, if your focus is on CRMs specifically, Merge doesn’t go as deep as Grid Squid — especially around complex objects and bulk sync.
Apideck provides a wide range of integrations across more than 50 categories, including CRMs. It’s especially well-suited for companies looking to build white-label marketplaces or embeddable integration hubs.
📈 Pricing is usage-based, starting at $299/month, scaling quickly with volume.
🔎 Watch out: Coverage is broad but not always deep — for CRM custom objects, Apideck may fall short.
Rutter is a strong option in fintech and commerce — with great schemas for orders, ledgers, and payouts — but it generally stays focused in this vertical and doesn’t support much else.
👍 If you’re syncing with commerce platforms or marketplaces, it’s a great pick.
👎 If you need CRM connections or other integrations, look elsewhere.
A newcomer on the scene, Unified.to boasts 281 integrations across many categories, including 33 CRMs. It positions itself for real-time, cache-less use cases and moves fast to add new connectors.
🧪 Still early-stage (founded 2024) — promising, but less proven than Grid Squid or Merge.
💲 Usage-based pricing starting at $350/month (50k API calls).
Nango appeals to dev teams who want code-first control and the option to self-host. It supports a wide range of APIs and CRMs, and offers Git-style versioning.
🧪 Still early in its development cycle, and support or SLA guarantees may be limited compared to more mature players.
🔎 Broad coverage of integrations across 25+ categories, but lacks depth for vertical-specific use cases.
Choosing a connector that “does it all” can be tempting, but users often only realize after they’ve committed to a provider that specific features they need aren’t supported for their connections — adding months of extra development time to build workarounds.
If you’re targeting a specific vertical, the buyer’s guide makes it clear: depth of specialization matters more than raw connector count. You want a platform that actually understands the data structures, quirks, and performance demands of your target market.
That’s why Grid Squid comes out on top for CRM integrations.
⚡ Want to see how Grid Squid handles CRM integration? Schedule a demo
📖 Want to explore the full comparison? Read the Filter Advisors 2025 Buyer's Guide to Integration Solutions and Software Connectors
