Custom Domain vs Approximated: a fair comparison

If you are evaluating Approximated for customer domains, or already run on it and want to know what else exists, this page puts the two products side by side. Credit first: Approximated is mature, capable infrastructure with real traffic behind it. This is not a takedown. The two products solve the same problem with different priorities, and the right choice depends on how much of the DNS step you want your customers to see, how you prefer to pay, and whether AI agents are part of your roadmap.

Everything below about Approximated comes from its public site and documentation as of July 2026. Details change, so treat their site as the source of truth for their side.

The short version

• Both products let your customers bring their own domains to your platform, with automatic TLS, an API, webhooks, monitoring, and an embeddable widget. The pattern itself is covered in bring your own domain.
• The biggest practical difference is who touches DNS. Approximated's standard flow asks your customer to point an A or CNAME record at your cluster, and its optional widget can automate that update at some providers. Custom Domain leads with one-click provider authorization across 63 DNS and registrar providers, so most customers approve a prompt instead of editing records.
• Pricing models differ. As of July 2026, Approximated charges $0.20 per domain per month with a $20 monthly minimum. Custom Domain has a free tier, with paid plans as you grow.
• Custom Domain ships an MCP server so AI agents can connect domains through the same flow. Approximated's documentation does not mention agent tooling as of July 2026.

What Approximated does

Approximated automates custom domains and SSL for SaaS platforms. When you sign up, it provisions a cluster: edge servers with a dedicated IP address that terminate TLS and proxy traffic to your application. Your customers point an A record at that IP for apex domains, or a CNAME at an intermediary subdomain, and Approximated verifies the record, issues a certificate, and keeps it renewed.

Around that core sits a serious feature set: a Virtual Hosts API with bulk operations, a DNS Checks API for validating records, webhooks with retries and idempotency keys, monitoring for DNS, certificates, and traffic, plus a WAF and DDoS protection at the edge. Edge Sequences let you match requests and apply rules before they reach your origin. There is also an optional embeddable DNS widget that detects a customer's DNS provider and offers one-click automatic updates where the provider supports it, falling back to instructions for that provider.

Approximated publishes its own scale figures: over a million custom domains served daily and a 99.993% average domain uptime, by its reporting. It has earned its reputation among builders who want usage-priced domain infrastructure.

What Custom Domain does

Custom Domain covers the same job with a different center of gravity: the moment a customer connects a domain. The product is a control plane plus a reverse proxy edge that terminates TLS, fully managed, with strict isolation between tenant platforms.

The connection flow is the headline. Your customer types their domain, Custom Domain detects the provider, and offers one-click provider authorization across 63 DNS and registrar providers. The customer approves, records are written for them, ownership is verified, a certificate is issued, and the domain is typically live in about 30 seconds. For providers outside that list, or customers who prefer doing it themselves, there is an API token flow and a guided manual flow that watches the records and verifies automatically. The mechanics are on how it works.

Integration comes in four forms: an embeddable connect widget with an SDK, a REST API covering connections, DNS records, TLS, monitoring, webhooks, and registrar search and purchase, a dashboard, and an MCP server so AI agents can connect domains with the same verification gates humans get. The full reference lives in the docs, and the feature list is on features.

Side by side

Capability	Custom Domain	Approximated
Automatic DNS configuration	One-click provider authorization across 63 DNS and registrar providers, plus API token and guided manual flows that verify automatically	Customer adds an A record to a dedicated cluster IP, or a CNAME; optional widget automates the update at supported providers, shows instructions elsewhere
Embeddable widget	Yes, connect widget plus SDK	Yes, optional DNS widget
API	REST API: connections, DNS records, TLS, monitoring, webhooks, registrar search and purchase	Virtual Hosts API with bulk operations, DNS Checks API, webhooks
TLS certificates	Automatic issuance and renewal at a managed edge	Automatic issuance and renewal on your cluster
Apex domains	Supported through the managed edge	Supported via A record to the cluster's dedicated IP
Time to live	About 30 seconds in the authorized flow	As fast as the customer completes the record change; certificates issue once records resolve
MCP server for AI agents	Yes	Not mentioned in its documentation as of July 2026
Monitoring and webhooks	Yes, both	Yes, both
Infrastructure model	Fully managed multi-tenant edge with strict isolation	Dedicated cluster with a dedicated IP, WAF, and DDoS protection
Pricing (as of July 2026)	Free tier from $0, paid plans on pricing	$0.20 per domain per month, $20 monthly minimum, volume discounts up to 50%, 400 GB bandwidth included, then $0.05 per GB; check their site for current pricing

The differences that matter

Who touches DNS

Approximated's core loop is simple and honest: your customer points a record at your cluster, and everything downstream is automated. The widget narrows the gap by detecting the provider and automating the update where supported. But the default experience for many customers is still pasting a record into a DNS panel, and the apex question still surfaces: A record for the root, CNAME for subdomains. If that distinction is new to you, read apex domain vs CNAME.

Custom Domain inverts the default. Provider authorization is the primary path across 63 providers, so the common case is a click and an approval screen, not a records editor. The guided manual flow covers everyone else, and it verifies automatically rather than asking the customer to come back and press a check button. If domain setup is a point where users stall in your onboarding, this difference is the whole ballgame. There is a longer walkthrough in our integration guide.

Pricing model

As of July 2026, Approximated charges $0.20 per custom domain per month with a $20 monthly minimum, automatic volume discounts of 5% for every 1,000 domains up to 50% off, and 400 GB of monthly bandwidth included, with overage at $0.05 per GB. That is transparent, predictable, and gets cheap at volume. Check their site for current pricing.

Custom Domain starts at $0 with a free tier, so you can integrate and ship before paying anything, then move up as connections grow. Details are on the pricing page. If you are optimizing pure per domain cost at tens of thousands of domains, model both against your real numbers. If you are starting smaller, or you value the DNS automation and registrar features being bundled, the free tier makes the evaluation cost zero.

AI agents and MCP

Custom Domain ships an MCP server, so an AI agent can search for a domain, purchase it, connect it, and verify it with the same gates a human gets in the dashboard. If your platform involves agents building sites or running workflows, that path is documented in connect domains with AI agents and on the AI agents page. Approximated's documentation does not mention MCP or agent tooling as of July 2026. That reflects a different roadmap, not a flaw, but if agents matter to you it is a real gap today.

Dedicated cluster versus managed multi-tenant edge

Approximated gives you a dedicated cluster and IP address, with a WAF, DDoS protection, and Edge Sequences for request rules. If you want your own IP and request manipulation at the edge, that is a genuine advantage. Custom Domain runs a fully managed multi-tenant edge with strict isolation between platforms: you never think about capacity, IP management, or certificate storage. How isolation works is covered in multi-tenant TLS. The tradeoff is control and a dedicated address on one side, zero infrastructure surface on the other.

When Approximated is the right choice

• You want a dedicated IP and your own cluster rather than shared infrastructure.
• You need request rules at the edge, or its built-in WAF in front of your origin.
• You run very large domain counts and its per domain price with automatic volume discounts models out cheaper for your traffic.
• Your customers are developers or agencies who edit DNS records without blinking, so automating that step buys you little.

When Custom Domain is the right choice

• Domain connection is part of onboarding and you want the common case to be one click, with the domain live in about 30 seconds.
• Your customers are not DNS people: think site builders, ecommerce platforms, and creator tools.
• You want registrar search and purchase in the same API, so a customer without a domain can buy one inside your product.
• AI agents create or manage sites on your platform and need to connect domains through MCP.
• You want to integrate free and pay only when usage grows.

Approximated vs Entri

People weighing Approximated usually look at Entri too, so the distinction among the three is worth drawing. Entri's core product automates the DNS configuration step: an embedded modal walks your customer through connecting at their provider, with SSL provisioning available through its Secure product and domain sales through Sell. As of July 2026, Entri does not publish pricing; you book a demo and get a quote. Approximated sits at the other end of the problem: it runs the hosting edge (cluster, dedicated IP, TLS, WAF) and traditionally leaves the DNS step to the customer, with its widget narrowing that gap. So "Approximated vs Entri" is often not a direct substitution question; they automate different halves of the same job.

Custom Domain covers both halves in one product: automated DNS through one-click provider authorization, and a managed TLS edge that actually serves the traffic, with published pricing that starts at $0. That is the honest case for it as an alternative to either. As always, verify the details on each vendor's site; all three products keep shipping.

How to run the evaluation

The cheapest test is empirical. Create a free account at app.customdomain.ai/signup, connect a test domain end to end, and time it. Read the docs next to Approximated's and judge which API maps more cleanly onto your stack. For the broader background, start with custom domains for SaaS and automating TLS for customer domains. And if you would rather talk it through against your architecture, book a demo.