About JSON → Ruby Hash

Convert JSON to a Ruby hash with symbol or string keys. Part of the DevTools Surf developer suite. Browse more tools in the Converters collection.

Use Cases

• Ruby developers converting JSON API responses into Ruby hash fixtures
• Rails developers generating seed data from JSON exports
• Backend devs pasting Ruby-compatible hash literals into IRB sessions
• QA engineers creating Ruby test data from JSON configuration files

Tips

• Paste JSON to get a Ruby hash with symbol or string key formatting
• Toggle between symbol keys (:name) and string keys ('name') for your preference
• null is converted to Ruby's nil and booleans remain lowercase

Fun Facts

• Ruby symbols (:name) are immutable, interned strings stored once in memory — using symbols as hash keys is faster than strings because comparison is by object ID.
• Ruby's hash rocket syntax (=>) was the only option until Ruby 1.9 (2007) introduced the JavaScript-like colon syntax ({ name: 'value' }) for symbol keys.
• Yukihiro 'Matz' Matsumoto designed Ruby in 1993 to be 'a language more powerful than Perl and more object-oriented than Python.' Ruby on Rails (2004) drove its mass adoption.

FAQ

Symbol keys or string keys?

Toggleable. Symbols (`:key => value`) are more idiomatic Ruby; strings (`"key" => value`) are safer when JSON keys have special characters.

Does it use the new `{key: value}` syntax?

When symbol keys are enabled and the JSON keys are valid Ruby identifiers, yes. Mixed keys fall back to the `=>` form.

What about Ruby-specific types?

Numeric strings pass through as strings (not auto-converted). Dates and times in ISO format stay as strings; convert with `DateTime.parse` in your code.

Can I output as a Struct instead?

No — this tool outputs a hash. For structs, use a JSON-to-class converter and hand-port the class definition.