Convert YAML to Properties Online
Spring Boot and most Java frameworks accept both application.yml and application.properties — but legacy systems, environment overrides and some deployment platforms still expect the flat .properties format. This converter flattens your YAML hierarchy into dotted keys (spring.datasource.url=...) so you can paste it straight into application.properties or pass it as -D system properties. Lists are joined with commas, nested maps become dotted paths.
YAML Converter - Convert Between Formats10 formats
Free YAML converter online. Convert YAML to JSON, XML, TOML, INI, Properties, CSV, and more. Also convert INI to YAML, TOML to YAML, and Properties to YAML. With automatic format detection.
Input (YAML)
Output (Properties)
Result will appear here
When you'd convert YAML to Properties
Real-world scenarios where this conversion is the right move.
Spring Boot configuration
Convert application.yml to application.properties when your platform or operator only supports the flat format.
JVM -D system properties
Generate -D arguments for java -jar invocations from a structured YAML source of truth.
Kubernetes ConfigMaps with --from-env-file
kubectl create configmap --from-env-file expects flat key=value pairs. Convert your YAML config to Properties first.
YAML vs Properties — what changes
Quick reference for the structural differences between both formats.
| Aspect | YAML | Properties |
|---|---|---|
| Structure | Hierarchical, indentation-based. | Flat, dotted keys like a.b.c=value. |
| Lists | YAML lists with - | Comma-separated values or indexed keys (list[0], list[1]). |
| Comments | # comments at any indentation. | # or ! comments, line-based only. |
| Types | Numbers, booleans, null distinguished. | Everything is a string — the app parses on read. |
Frequently asked questions
Does it work with Spring Boot application.yml?
Yes — that is the most common use case. Nested keys flatten correctly to spring.datasource.url, server.port and so on.
How are YAML lists converted?
Short string lists become comma-separated values. Lists of objects flatten with indexed keys (servers[0].host, servers[1].host).
Are environment variable placeholders preserved?
Yes. ${DB_PASSWORD} stays as ${DB_PASSWORD} in the output so Spring Boot resolves it at runtime.
What about multi-line strings?
YAML multi-line strings (| or >) are joined with \n escapes so they fit a single line=value entry.
Other conversions
Hop into another conversion that shares one of these formats.