About SOAP Request Builder

Build and simulate SOAP XML requests. Part of the DevTools Surf developer suite. Browse more tools in the API / Config collection.

Use Cases

• Build a SOAP request envelope for a legacy enterprise system that has not been migrated to REST.
• Test a payment gateway or healthcare API that exposes a SOAP endpoint.
• Debug a SOAP fault by constructing minimal requests to isolate which parameter causes the error.
• Document SOAP request structure for a third-party integration guide.

Tips

• Always fetch the WSDL before building a request — the WSDL defines namespaces, operation names, and parameter types that must exactly match for the server to parse the envelope.
• Test with SOAPAction header present — many SOAP servers require this HTTP header to route requests to the correct operation; missing it returns a generic fault.
• Wrap string values in CDATA blocks if they may contain XML special characters — unescaped <, >, and & inside SOAP body elements cause parse failures.

Fun Facts

• SOAP (Simple Object Access Protocol) was originally designed by Dave Winer, Don Box, Bob Atkinson, and Mohsen Al-Ghosein at Microsoft in 1998. The name is somewhat ironic — SOAP is one of the more complex web communication protocols.
• SOAP over HTTPS using WS-Security became the dominant enterprise integration protocol in the early 2000s, before REST APIs began displacing it starting around 2007–2010.
• SOAP is still widely used in banking, healthcare (HL7 SOAP), government systems, and insurance — industries where its formal contract (WSDL) and built-in security (WS-Security) remain valuable.

FAQ

Why does my SOAP request return a fault?

Common causes: incorrect namespace URI, missing or wrong SOAPAction header, malformed XML (unclosed tags, special characters), incorrect operation name case, or authentication header format mismatch.

SOAP vs. REST — which should a new API use?

REST for new APIs, almost always. SOAP remains appropriate when you need formal contracts (WSDL), WS-Security standards, or when integrating with enterprise systems that mandate SOAP (SAP, legacy banking, healthcare HL7).