I built Blobster, a local-first structured data workbench for Chrome

Hein Dauven — Sun, 21 Jun 2026 16:53:21 +0000

I built Blobster as a small side project because reviewing and editing CSV, Markdown, JSON and other structured files in the browser was more annoying than it should be.

I kept running into the same workflow: open a raw API response, inspect a CSV export, preview Markdown, search through a blob, copy a path or value, maybe redact something sensitive before sharing it.

Most tools either felt too narrow, too paste-site-like or required sending data somewhere I did not want to send it.

So Blobster is a local-first extension for inspecting structured data directly in the browser.

It supports:

CSV / TSV table viewing and editing
JSON tree, table and raw views
Markdown preview and editing
Search across keys, values, and cells
Copying values, JSONPath, jq and JS paths
Redacted copy for sensitive-looking output
Local browser usage with no login

Everything stays local. No uploads, no account, no telemetry.

Chrome Web Store: https://chromewebstore.google.com/detail/blobster/epddolhfilamhbnmgglenceabjbbeeho

I would love feedback from people who often inspect API responses, data exports, configs, logs, HAR files or random structured blobs in the browser.

DEV Community: Hein Dauven

I built Blobster, a local-first structured data workbench for Chrome