Braceview

Double-
click anything.

That's the whole app. JSON, CSV and Markdown files, on screen in about a second. Offline, free, no account. Try the files below, or drop your own on this page. It never leaves the tab.Tap a file below to open it.

braceview.json

{
"opens": [".json", ".jsonl", ".csv", ".tsv", ".md"],
"uploads": 0,
"account": null,
"telemetry": false,
"runs_on": {
}
}
In the app: a small JSON is on screen 982 ms after a cold start

benchmarks.csv

Collapse allJSON 20 MB7
Scroll jumpCSV 1M rows16
JSONPath queryJSON 20 MB71
Clear filterCSV 1M rows95
Sort text columnCSV 1M rows248
Column statisticsCSV 1M rows347
SearchJSON 20 MB431
Launch the appno file840
Open, cold startJSON 20 MB1760
Open, cold startCSV 1M rows2390
Ryzen 5 7530U laptop · method · click a column to sort

why.md

I just wanted to read the file

Someone sends response.json. Two lines. Double-click, and an IDE starts loading extensions, indexing a workspace and asking about an update.

So I built the thing that only opens the file.

In the app: Markdown text is readable 1.10 s after a cold start

Get Braceview

Free. No trial, no account.

"why"

I just wanted toread the file.

Someone sends you response.json. Two lines. You double-click it, and an IDE wakes up: extensions, workspace index, an update prompt. All that to read two lines. Braceview is the small thing that only opens the file, then gets out of the way.

"json"

Find the value,not the bracket.

JSON tree with a JSONPath query in dark mode

"csv"

A million rows,no waiting.

CSV table sorted by score with column statistics

"markdown"

Reports that looklike reports.

Braceview showing a Markdown report with a table and a flow diagram

"chrome"

The same viewer,in your browser.

Braceview extension showing JSON from a documentation page as a tree

"speed"

This line isone second long.

watch what fits inside it. measured on a Ryzen 5 7530U laptop, not a workstation

  1. 95 msclear a filter on 1M rows
  2. 248 mssort 1M CSV rows
  3. 347 mscolumn stats on 1M rows
  4. 431 mssearch a 20 MB JSON
  5. 840 msapp launched
  6. 982 mssmall JSON on screen, from cold
248msto sort a million CSV rows
1.76sfrom launch to a 20 MB JSON tree
0%CPU while it sits open
16msto jump anywhere in a million rows
Open a 1M-row, 55 MB CSV2.39 s
JSONPath query, 20 MB JSON71 ms
Expand all, 20 MB JSON75 ms
Find in a 600-section Markdown270 ms
Open a 600-section Markdown2.14 s

method, machine and every number: BENCHMARKS.md

"uploads"

0

files are read on your machine. there is no server to send them to

"account"

null

no sign-up. settings stay on your device

"telemetry"

false

no analytics, no tracking, works offline

"get_it"

Free, everywhere.

version 1.2.1 · release notes · price: 0

Microsoft Store "windows"

Windows 10 and 11, automatic updates. Or: installerportable, no install

Chrome Web Store "chrome", "edge"

JSON, CSV and Markdown pages, right in the browser. install the zip instead

"faq"

Questions.

Windows says “Windows protected your PC”

The installer isn't code-signed yet, so SmartScreen doesn't recognise it. Click More info, then Run anyway. The Microsoft Store version doesn't show this warning.

macOS says the app “can't be opened” or “Apple could not verify it”

Braceview isn't notarized by Apple yet. To open it the first time:

  1. Drag Braceview to Applications and open it once. You'll see the warning. Click Done.
  2. Open System Settings → Privacy & Security, scroll down and click Open Anyway next to Braceview.
  3. Confirm with your password. After that it opens normally.
How do I open files with Braceview by double-clicking?

Windows: right-click a .json, .md or .csv file → Open with → Choose another app → Braceview → tick Always. Mac: right-click a file → Get Info → Open with → Braceview → Change All.

How do I install the extension without the Chrome Web Store?

Easiest is the Chrome Web Store listing. To load the zip by hand instead:

  1. Unzip braceview-extension-*.zip to a folder you'll keep.
  2. Open chrome://extensions (or edge://extensions) and switch on Developer mode.
  3. Click Load unpacked and choose the folder. For local files, open Details and enable Allow access to file URLs.
Why can't the extension show some CSV links?

Chrome always downloads files that a website sends as text/csv, before any extension can see them. CSV files served as plain text, like raw files on GitHub, open in Braceview.

Is it really free?

Yes. No trial, no account, no ads.

I found a bug or want a feature

Please open an issue on GitHub.