The cheapest esignature api for saas is the one you own.
Stop paying a success tax on every document your users sign. Host DocuSeal on Opsily for a flat monthly fee. Unlimited envelopes, unlimited signers, zero per-signature costs.
Trusted by fast-moving teams
Why your current eSignature API is killing your margins
Most eSignature providers charge you like a utility, but they price like a luxury. They call it per-envelope pricing. We call it a success tax.
As your SaaS grows, your bill grows. If you send 100 documents a month, it is an annoyance. If you send 10,000, it is a line item that eats your profit. SaaS founders often find themselves stuck with legacy providers like DocuSign or PandaDoc because the integration is already done. They pay thousands of dollars a year for a service that should cost pennies.
The Developer Reality
Enterprise APIs are often gated behind sales calls. You want to test an endpoint? Talk to an account executive first. You want to go live? Sign an annual contract with a minimum volume commitment. This is the opposite of how modern SaaS is built.
DocuSeal changes this dynamic. It is open-source. It is API-first. It is designed for developers who need to build signing workflows into their products without the corporate friction. By hosting DocuSeal on Opsily, you get the cheapest esignature api for saas because you only pay for the compute, not the signatures.
The cheapest esignature api for saas with flat-rate hosting
Scale your SaaS without worrying about your next eSignature bill. Opsily provides the infrastructure for the cheapest esignature api for saas: you provide the documents.
Flat-Rate Hosting
We do not care if you send one document or one million. Your price stays the same. This is the only way to achieve the cheapest esignature api for saas at scale. No hidden fees, no per-user surcharges, just a stable server cost you can budget for.
Data Sovereignty
Keep your sensitive legal data in your own environment. Choose your region and stay GDPR compliant. Unlike multi-tenant SaaS providers, your documents live on your dedicated Opsily instance. You own the database and the storage, ensuring your customers' privacy is never compromised.
Full API Control
Access the full DocuSeal REST API without limits. Integrate webhooks, manage templates via code, and embed signing frames directly into your application. You get enterprise-grade features without the enterprise sales cycle. It is the raw power of open source with the reliability of managed hosting.
How the math changes at scale
Monthly cost comparison based on 1,000 envelopes per month for a growing SaaS platform.
Legacy pricing estimated based on standard enterprise API tiers. Opsily pricing based on Medium plan.
EUR 800 a year for tools that used to cost us multiples of that. We replaced HubSpot, Make.com, and our password manager with self-hosted apps on Opsily. One provider, one fee.
Franz Koller
Co-Founder · Joy
Built for SaaS Product Teams
We don't gatekeep features. Every Opsily plan supports the full capabilities of DocuSeal, optimized for production SaaS environments.
Deploy your API in minutes
Choose Your App
Select an app to get started.
Select DocuSeal
Choose DocuSeal from the Opsily app catalog. No configuration files or complex setup scripts needed.
Launch Server
Pick your server size. Our Medium plan is recommended for most SaaS APIs handling consistent traffic.
Configure & Integrate
Get your API key instantly. Use our documentation to embed the signing flow into your app in under an hour.
Scale with Confidence
As your user base grows, your costs stay flat. Focus on building features, not managing signature credits.
Simple, Transparent Pricing
No per-signature fees. No hidden costs. Choose the server that matches your SaaS volume.
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Enterprise Security for your SaaS
Self-hosting doesn't mean sacrificing security. Opsily provides the hardened infrastructure required for legal documents.
GDPR Ready
All servers are located in Germany. Data never leaves the EU, making it the perfect choice for B2B SaaS builders.
Daily Backups
Automated, encrypted backups of your DocuSeal database and documents. Recovery is a one-click process.
Dedicated Compute
Your instance is yours alone. No shared resources. No noisy neighbors impacting your API response times.
SSL Encryption
Automatic Let's Encrypt SSL certificates for every deployment. All document traffic is encrypted in transit.
Frequently Asked Questions
Yes, because it fundamentally changes the cost structure. Traditional APIs charge $1 to $5 per document sent. With Opsily hosting DocuSeal, you pay a flat monthly fee for the server. If you send 1,000 documents, your cost per document is roughly $0.03. If you send 10,000, it drops to $0.003. No other provider can match this math at scale.
What our customers say
Teams across the EU run their stack on Opsily. Here is what that looks like in practice.
EUR 800 a year for tools that used to cost us multiples of that. We replaced HubSpot, Make.com, and our password manager with self-hosted apps on Opsily. One provider, one fee.
Franz Koller
Co-Founder • Joy
We were paying per user on everything and it added up fast. Now we run five apps for less than one of those old plans. My finance team finally stopped asking questions.
Elise
Head of Operations
Wanted to use n8n for ages but the self-host part always stopped me. Opsily just handled it. Got the power without becoming an IT person overnight.
Federica B.
Automation Consultant
Ready to lower your SaaS burn?
Deploy DocuSeal on Opsily today and get the cheapest esignature api for saas. Start for free and scale without limits.