MockServer
Beeceptor
Request inspector
HttpMaster
Webhook.site
Hoppscotch
API Fortress
CurlHub.io
LeapRows
Row Zero
Microsoft Office Excel
Google Sheets
TablePlus
Beekeeper Studio
HowToCSV
Sigma Computing
LeapRows is a blazing-fast, browser-based CSV analysis tool powered by DuckDB-WASM. It handles 1,000,000+ rows directly in your browser โ no server uploads, no Python setup, no file splitting required.
All processing happens locally on your device using WebAssembly (WASM) and the Origin Private File System (OPFS). Your data never leaves your browser, making it ideal for teams with strict data privacy requirements.
Key features: 1M+ row support โ break the Excel/Google Sheets row limit without splitting files Private by design โ zero data upload; all analysis runs on your device Smart JOIN โ merge multiple CSV files on multiple keys without SQL Instant pivot & aggregation โ real-time charts and tables, no spinning wheel Recipes โ save your data prep steps as reusable JSON workflows and share them with your team Presets โ regex extraction, ranking, URL parameter parsing via GUI, no code needed Parquet support โ upload or export in Parquet format for faster repeat analysis
LeapRows is built for data analysts, marketers, and sales ops professionals who need spreadsheet-level simplicity at database-level scale โ without waiting for an engineering ticket.
MockServer
LeapRowsLeapRows's answer:
LeapRows's answer:
LeapRows is a fully local, browser-based data tool powered by DuckDB-WASM that handles 1M+ row CSV files with blazing speed โ no server, no uploads.
LeapRows's answer:
LeapRows's answer:
LeapRows was born out of two frustrations: the "Python sharing problem" and server costs.
As an in-house SEO specialist, I frequently work with large CSVs exported from tools like Ahrefs, Google Search Console, and BigQuery โ often hundreds of thousands of rows. For heavy lifting, I'd reach for Python (Polars), but Python has a steep barrier: environment setup, code adjustments, and a learning curve that made it impossible to share with non-engineer teammates.
Even for myself, I'd often think "do I really need to write Python just for this small transformation?" On top of that, frustrating edge cases โ like type inference inconsistencies causing join errors on the same CSV from the same tool โ kept piling up.
I wanted something as easy as a spreadsheet but capable of handling millions of rows. That's what LeapRows is.
LeapRows's answer:
DuckDB-WASM, OPFS๏ผOrigin Private File System๏ผ
LeapRows's answer:
Based on our record, MockServer should be more popular than LeapRows. It has been mentiond 4 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
There are several strategies to solve this kind of challenge, but today we will see MockServer as a tool to resolve it. - Source: dev.to / almost 2 years ago
The open-source examples are mockoon, mock-server.com, etc. Source: over 3 years ago
I've just found out MockServer and it looks awesome ๐คฉ so I wanted to check it out repeating the steps of my previous demo WireMock Testing which (as you can expect) uses WireMock, another fantastic tool to mock APIs. - Source: dev.to / about 4 years ago
I tend to use MockServer. With MockServer you can define inputs, so you can say that the request should look like this with that URL, etc etc. That way you can verify that the request looks okay. Source: over 4 years ago
I use this setup on LeapRows, a browser-based CSV tool I built on Vercel. - Source: dev.to / 5 months ago
Beeceptor - Unblock yourself from API dependencies, and build & integrate with APIs fast. Beeceptor helps you build a mock Rest API in a few seconds.
Row Zero - Row Zero is the best spreadsheet for big data. Row Zero has all the spreadsheet features you know and love, but can handle 1+ billion rows, process data faster, connect live to your data warehouse and supports sharing.
Request inspector - Debug web hooks, http clients
Microsoft Office Excel - Microsoft Office Excel is a commercial spreadsheet application.
HttpMaster - HttpMaster is a professional software tool for testing and debugging HTTP applications, primarily aimed at REST API applications and web services.
Google Sheets - Synchronizing, online-based word processor, part of Google Drive.