About

Data serialization often results in redundant information. API responses frequently include fields with null values that consume bandwidth without adding semantic value. This utility addresses payload bloat by parsing the JSON structure and recursively pruning properties where the value is explicitly null. It ensures that nested objects and arrays are traversed fully. Removing these keys reduces the overall message size. This is particularly critical for mobile applications with limited data plans or high-frequency trading systems where latency is paramount. The tool handles deep nesting scenarios typically found in complex graph data or legacy system exports.

Formulas

The sanitization logic can be described as a recursive function Clean applied to a node n within the JSON tree structure.

{

Clean(v) for each k,v in n if v ≠ nullnull if n is nulln otherwise

When n is an Array, the function maps over elements e such that e ∈ n. The removal of nulls within arrays changes the indices of subsequent elements. This behavior is togglable based on strict adherence to schema definitions versus aggressive size optimization.

Reference Data

Data Type	Action	Condition	Result Example
Object Property	Remove Key	Value is null	{"id": 1, "v": null} → {"id": 1}
Array Element	Filter Item	Value is null (Optional)	[1, null, 2] → [1, 2]
Nested Object	Recurse	Contains children	Traverses down tree
Empty Object	Preserve	Result is {}	Keeps structure valid
Empty String	Keep	"" is not null	No change
Boolean	Keep	FALSE	No change
Number	Keep	0	No change
Undefined	Ignore	Invalid in JSON spec	Parse Error

Frequently Asked Questions

No. Modern JavaScript engines preserve insertion order for non-integer keys. However, JSON is technically unordered. If your application relies on specific key ordering, you should verify if that dependency is necessary.

By default, the tool inspects objects inside arrays but keeps nulls as elements to maintain index integrity. You can enable "Filter Arrays" to remove null elements entirely, which reduces size but shifts indices.

If an object contains only null values, removing them results in an empty object {}. The tool preserves this empty object to ensure the structural type remains consistent for parsers expecting an object.

The browser memory limits the operation. Processing files larger than 10MB may cause temporary freezing. The algorithm is synchronous to ensure data integrity during the recursive sweep.

No. The input must be syntactically valid JSON. Standard JavaScript objects (keys without quotes) or trailing commas are not valid JSON and will trigger a parse error.