Flatten nested JSON into a single-level dot-notation object. JSON Flattener is a free online tool from the ToolsRift JSON Tools collection. It runs entirely in your browser — nothing to install, no signup, and your data never leaves your device.
Paste nested JSON and it is collapsed into one flat object where each key is the full dot-notation path to its value.
A single-level object whose keys are paths like user.address.city, each mapping to the original leaf value.
Array items use bracket or dotted index notation, such as items.0.name, so every element remains addressable.
Yes — use the JSON Unflattener to expand dot-notation keys back into nested objects.