JSON Converter Tools

23 tools · free · nothing uploaded

Every converter here runs both directions and each direction has its own page, because the options that matter going out are not the options that matter coming back. Nothing is uploaded: the file is read by the tab, converted in the tab, and downloaded from the tab.

Start here

JSON → CSV Array of objects to CSV, with a column picker and a choice of how to flatten nesting. CSV → JSON CSV back to objects, guessing numbers, booleans and nulls so you do not post-process. JSON → YAML Block or flow style, key order kept, and a warning when a value hits the Norway problem. YAML → JSON YAML 1.2 with anchors and merge keys resolved rather than left as references. JSON → Excel A real .xlsx workbook — typed cells, frozen header row — not a CSV with the wrong suffix. JSON → XML Pick how keys become attributes and how arrays repeat, instead of accepting one convention.

Everything else in Convert

JSON → TSV — Tab-separated output for spreadsheets and Postgres COPY.
TSV → JSON — Tab-separated text to a JSON array.
XML → JSON — XML to JSON with attribute and text-node control.
JSON → TOML — Tables and array-of-tables for pyproject / Cargo.
TOML → JSON — TOML config to JSON.
JSON → NDJSON — Flatten an array into one object per line.
NDJSON → JSON — Collect newline-delimited JSON into one array.
JSON → Base64 — Standard or URL-safe Base64.
Base64 → JSON — Decode and pretty-print Base64 payloads.
JSON ↔ MessagePack — Encode to MessagePack bytes and decode them back, hex or base64.
JSON ↔ CBOR — Encode to CBOR (RFC 8949) and decode it back, hex or base64.
MongoDB Extended JSON — ObjectId, ISODate and $oid / $date documents to plain JSON and back.
JSON → HTML table — Semantic <table> markup you can paste into a page.
JSON → Markdown table — GitHub-flavoured pipe table for READMEs and tickets.
HTML table → JSON — Scrape a pasted <table> into a JSON array.
JSON → ES bulk — Elasticsearch / OpenSearch _bulk NDJSON request body.
JSON → HCL — Terraform configuration syntax with heredocs.

Why these run in your browser

There is no server-side processing here and no upload step: the page loads, and from then on the parsing, converting and rendering happen in this tab using your machine's CPU. That has three consequences worth knowing about. Your data stays on your machine, which matters when the JSON is a production payload with real customer records in it. There is no file-size limit imposed by us, only by how much memory your browser will give the tab. And once the page has loaded, it keeps working with the network off.

The trade is that very large documents are bounded by browser memory rather than by a beefy server — somewhere past 50 MB a textarea gets sluggish, and dropping the file in is better than pasting it. The privacy page spells out what is and is not collected.