SignatureAPI API Alternative

SignatureAPI Alternative
Official SDKs + Document Automation

SignatureAPI offers webhook libraries. TurboSign gives you official SDKs in 5 languages, n8n integration for no-code workflows, document generation, and a generous free tier.

Start Building Free Read the Docs

5free/month

99.9%uptime SLA

5 SDKsTS, Python, PHP, Go, Java

Why Developers Choose TurboSign Over SignatureAPI

Both offer clean APIs, but TurboSign adds SDKs, document automation, and a free tier.

Official SDKs

TurboSign

TS, Python, PHP, Go, Java with types

SignatureAPI

Webhook libraries only

Document Generation

TurboSign

TurboDocx + TurboSign in one API

SignatureAPI

Signatures only

Free Tier

TurboSign

5 signatures/month

SignatureAPI

No free tier

Webhooks

TurboSign

Real-time webhook notifications

Open Source

TurboSign

Home of html-to-docx — we know documentation

Pricing

TurboSign

We'll match or beat + free tier

SignatureAPI

$0.25/env ($0.10 at scale)

SignatureAPI is Great for Signatures — TurboSign Does More

SignatureAPI offers a clean REST API focused on eSignatures with competitive per-envelope pricing. If you only need signature functionality, it's a solid choice.

TurboSign is built for developers who need complete document workflows:

Official SDKs in TypeScript, Python, PHP, Go, and Java with full types
Document generation + signatures — create contracts from templates and send for signature in one API
Free tier — 5 signatures/month to test and develop, no credit card required
Price match guarantee — we'll match or beat SignatureAPI's pricing
Web UI included — non-developers can use TurboSign directly; see product comparison

Start Building in Minutes

Choose between our TypeScript SDK for the best developer experience, or use our REST API directly.

send-signature.ts

import { TurboSign } from '@turbodocx/sdk';

// Configure SDK with your credentials
TurboSign.configure({
  apiKey: process.env.TURBODOCX_API_KEY,
  orgId: process.env.TURBODOCX_ORG_ID,
});

// Send for signature using template anchor tags
const result = await TurboSign.sendSignature({
  fileLink: 'https://example.com/contract.pdf',
  documentName: 'Service Agreement',
  recipients: [
    { name: 'John Doe', email: 'john@acme.com', signingOrder: 1 }
  ],
  fields: [
    {
      type: 'signature',
      recipientEmail: 'john@acme.com',
      template: {
        anchor: '{SignHere}',
        placement: 'replace',
        size: { width: 200, height: 50 },
      },
    },
    {
      type: 'date',
      recipientEmail: 'john@acme.com',
      template: {
        anchor: '{DateHere}',
        placement: 'replace',
        size: { width: 150, height: 30 },
      },
    },
  ],
});

// Returns: { success: true, documentId: "...", message: "..." }
// Recipients automatically receive signing invitation via email