EtherCalc

Active

Country: Taiwan (TW)
Founded: 2012
Developer: Audrey Tang (individual developer from Taiwan)
Pricing: Free (open-source)
Open source: Yes
Platforms: Web

Indexes

Spreadsheets

Overview

EtherCalc is a web-based spreadsheet application that enables real-time collaborative editing by multiple users without requiring accounts or logins. Data is saved on the web, with changes instantly reflected across all open sessions, supporting uses like accounting, inventory, scheduling, and list management. It stands out as an open-source alternative to tools like Google Sheets, emphasizing no-login access and self-hosting capabilities via its server software.

Key Features

Real-time collaboration - Multiple users edit the same spreadsheet simultaneously with instant updates on all screens.
No account required - Users access and collaborate via unique shareable URLs without sign-ups.
Mathematical functions - Supports formulas, dates, text functions, and calculations like SUM.
Text formatting - Includes options for colors, background, and conditional formatting.
Import capabilities - Accepts CSV, Excel, and ODS file uploads.
REST API - Provides API for programmatic access and integration.
Export options - Exports to CSV, JSON, HTML, Markdown, and Excel formats.

Pricing

Plan	Price	Includes
Free	Free	Unlimited spreadsheets, real-time collaboration, no account needed.
Self-hosted	Free (open-source)	Full server deployment for private instances.

Platforms & Requirements

EtherCalc runs in any modern web browser on desktops, laptops, tablets, or mobiles with internet access. No client software installation is required. Limitations include dependency on server availability and potential cell limits around 500,000 per spreadsheet.

Integrations & Ecosystem

REST API
CSV import/export
Excel import/export
ODS import
JSON export
HTML export
Markdown export
R package (ethercalc)

Alternatives

App	Difference
Google Sheets	Requires Google account and has editing locks; more advanced features but less privacy-focused.
Etherpad	Text-only collaborative editor, lacks spreadsheet functions and formulas.
CodiMD	Markdown-focused collaboration, no grid-based spreadsheet support.
OnlyOffice	Full office suite with account system; supports self-hosting but heavier resource use.

Reputation

EtherCalc is regarded as a reliable, lightweight option for quick collaborative spreadsheets without accounts, praised for its simplicity and open-source nature. Users appreciate real-time editing and ease of sharing via URLs, though some note its dated interface and limited advanced features compared to modern tools. Instances remain active as of 2026, with ongoing development including a TypeScript rewrite.

Sources (10)