JSON Size Analyzer
Analyze a JSON document by byte size — find the heaviest keys and arrays.
Total: 348 bytes
(root)object291B84%
(root).usersarray214B61%
(root).users[0]object124B36%
(root).users[1]object87B25%
(root).users[0].biostring58B17%
(root).metadataobject55B16%
(root).users[1].biostring27B8%
(root).metadata.generatedstring22B6%
(root).users[0].emailstring19B5%
(root).users[1].emailstring17B5%
(root).users[0].namestring15B4%
(root).users[1].namestring11B3%
(root).users[0].idnumber1B0%
(root).users[1].idnumber1B0%
(root).metadata.totalnumber1B0%
(root).metadata.pagenumber1B0%
How JSON size analysis works
Each node in the JSON tree is serialized to a JSON string and measured in UTF-8 bytes. The root is always the largest (it contains everything), and nested values are ranked below it. Strings, arrays, and objects that dominate the total size stand out immediately, helping you find the best candidates for trimming API responses.
To format and validate JSON, use JSON Formatter. To compare two JSON documents, try JSON Diff Checker. To explore structure visually, see JSON Tree Viewer.
Private & free — this tool runs entirely in your browser.
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