Best Sym Alternatives & Competitors in 2025

Cal.com (formerly Calendso) is the open source Calendly alternative.

Key Cal.com features:

Customizable Open-source Integrations User-friendly Interface

Open Source

Simplifying cloud hosting. Deploy an SSD cloud server in 55 seconds.

Key DigitalOcean features:

Ease of Use Cost-Effective Scalability Performance

paid $5.0 / Monthly (1 GB / 1 vCPU / 25 GB)

Clear, Fast & Unlimited. Residential & Mobile Proxies For Best Price.

Key ASocks features:

HTTP Socks5 ASN targeting Pay as you go

Try for free paid Free Trial $3.0 (3$ per 1 Gb)

Power your product notifications with Segment and Hightouch.

Key Knock App features:

User-Friendly Interface Seamless Integration Comprehensive Analytics Time-Saving Automation

Opta is a new kind of Infrastructure-As-Code framework designed for fast moving startups.

Key Opta features:

Comprehensive Data Real-Time Updates Integration Capabilities Customizable Solutions

One-click RAG deployment for developers

Making cloud-native and serverless dev fun and productive

Key Nitric features:

Improved Developer Experience Multi-cloud Compatibility Serverless Architecture Built-in Security Features

Open Source

A practical guide to interviewing customers

Calendar and scheduling for teams

Key Sunsama features:

User-Friendly Interface Task and Calendar Integration Focus on Deep Work Collaboration Features

Deploy in less than 5s

Key Codesphere features:

Ease of Use Integrated Development Environment Scalability Collaboration

A scheduling tool both the sender and the recipient will love.

Key SavvyCal features:

User-Friendly Interface Calendar Integrations Customization Options Time Zone Detection

freemium $12.0 / Monthly (The Basic Plan)

Optimize your schedule with custom booking pages and calendar integrations

Key TidyCal features:

Affordability User-Friendly Interface Integration Capabilities Customizable Booking Pages

freemium $29.0 / One-off ($29 one-time paymnet)

GitHub for research and data science

Key Amie features:

User-Friendly Interface Comprehensive Feature Set Integration Capabilities Cross-Platform Availability

Research Malicious Infrastructure - Securely and At Scale