Developer Tools

ViewKit logo

ViewKit

Free in-browser viewer for scientific and ML data files

0 votes. Log in to vote for ViewKit as a buyer Follow vendor. Log in to follow ViewKit as a buyer

A free online viewer for HDF5, Parquet, Zarr, Arrow, CSV, Excel, NumPy, safetensors and other data files that runs entirely in your browser.

Overview

The ViewKit homepage

ViewKit is a free tool for viewing scientific and machine-learning data files directly in your browser without uploading them anywhere. It supports HDF5, Parquet, Zarr, Apache Arrow and Feather, CSV and TSV, Excel, JSON Lines, NumPy, safetensors, TFRecord, WebDataset and audio files. All parsing happens locally using WebAssembly and JavaScript, so file contents never leave your device and you can work offline after the page loads.

Built for ML researchers and data scientists, ViewKit eliminates the need to write throwaway Python scripts, spin up notebooks, or upload files to external sites. You can open a file immediately without installing anything or creating an account. The tool handles very large files efficiently by only reading the bytes you are viewing.

Capabilities

Browse HDF5 groups, datasets and attributes
Read Parquet schemas, row groups and column statistics
Open Zarr v2 and v3 stores from a folder or a zip
Inspect Apache Arrow and Feather files
View CSV, TSV and Excel spreadsheets
Load NumPy .npy and .npz arrays
List safetensors tensors and step through TFRecord records
Slice N-dimensional arrays and render heatmaps
Parse every file locally, with no upload
Work offline after page loads

Pricing

Free

Follow vendor. Log in to follow ViewKit as a buyer

Follow ViewKit to get an email when they post a milestone, ship a new product or add a demo video.

ViewKit fact sheet

Community votes	0
Website	viewkit.app

ViewKit metrics

Vendor metrics for viewkit.app: Ahrefs Domain Rating and Majestic link data, with the delta since the last review.

Domain Rating: 0; no change since last check
Trust Flow: 0; no change since last check
Citation Flow: 22; no change since last check
Referring domains: 20; no change since last check
External backlinks: 54; no change since last check

Vendor Domain Rating (Ahrefs) checked 6 Nov 2026, spec changed 1 Nov 2026. Vendor Majestic data checked 1 Nov 2026, spec changed 1 Nov 2026. Link metrics supplied by Majestic. Trust Flow, Citation Flow and Topical Trust Flow are trademarks of Majestic-12 Ltd.

ViewKit vendor domain

Open the vendor record

We read this from the registry's RDAP record on 5 Nov 2026, 22:35 UTC.

Domain age: 4 months
Registered: 6 Jul 2026
Expires: 6 Jul 2027
Registrar: CloudFlare, Inc.
DNSSEC: Not signed

Vendor domain report: viewkit.app

ViewKit post-launch report

Measured after ViewKit went live on SaaS Directory Pro on 1 November 2026.
Measure	At launch, then latest
Domain Rating (Ahrefs)	0 to 0 no change since launch 1 Nov 2026, then 5 Nov 2026
Trust Flow (Majestic)	0 first measured 1 Nov 2026
Referring domains (Majestic)	20 first measured 1 Nov 2026

Day 4 since launch. Next receipt: day 30, 1 Dec 2026. Many things move these figures, so a change is not proof of cause. Only stored readings are shown.

Biggest gains on SaaS Directory Pro

About to launch?

Plan your launch with our free playbook, from preparing your listing to choosing more launch directories.

The week before
On the day
Week one
Beyond launch

Read the free playbook

Compare and explore

See the alternatives to ViewKit, Castov vs ViewKit, ViewKit vs SysEdge, Design Extractor vs ViewKit, Octri.dev vs ViewKit, Keep Mac Awake vs ViewKit, LetsDeployIt vs ViewKit, more in Developer Tools.

Buyer questions

Where do my files go?

Files stay on your computer. ViewKit reads and renders each file locally in your browser, so the contents are never uploaded or sent to a server. Once the page has loaded, you can even go offline.

How does it open files that are too big to upload?

It only reads the part you are looking at, straight from the file on your disk. Scroll to a new region and it fetches just those bytes, so multi-gigabyte files open in about a second.

Do I need an account?

No. There is nothing to install and nothing to sign up for. Open the viewer, drop a file in, and it opens.

Is ViewKit free?

Yes. Open as many files as you like.

Who is ViewKit for?

ViewKit is built for ML researchers and data scientists who open files like these all day. The usual ways to peek inside one are a chore: write throwaway Python, spin up a notebook, or upload the file to some random site.

Leave a review for ViewKit

No customer reviews of ViewKit yet. Write the first. Customer reviews are free and nobody can buy them.

Read customer reviews

Compare with

Alternatives to ViewKit
#	Product	DR	Votes
1	Swastik CodesWeb-based API platform for designing, testing, mocking, monitoring and documenting REST, GraphQL, gRPC, WebSocket, MQTT and MCP APIsDeveloper ToolsIndia	2 no change since last check	0 votes. Log in to vote for Swastik Codes as a buyer
2	ValidateHTMLHTML validation API and free online validator for deployed pagesDeveloper ToolsFrance	9 no change since last check	0 votes. Log in to vote for ValidateHTML as a buyer
3	BuildFerryInstall iOS builds on any iPhone with one linkDeveloper Tools	0 no change since last check	0 votes. Log in to vote for BuildFerry as a buyer
4	FiveM Backdoor ScannerFree browser-based scanner to detect hidden code, loaders and credentials in FiveM resourcesDeveloper Tools	29 no change since last check	0 votes. Log in to vote for FiveM Backdoor Scanner as a buyer