Sync your calendars, avoid scheduling conflicts
OneCal syncs Outlook, iCloud, and Google Calendars in real-time so you don’t get double-booked, lets you share easy-to-use scheduling links, and helps you manage all your calendars in a unified calendar view.
Trusted, Secure, and Compliant
- GDPR compliant
- DPA included

- SOC 2 (Type II)
- Certified
- Trust Center
- Security docs on request
You are in good company. OneCal is trusted by thousands of users from organizations like
Sync Multiple Calendars & Simplify Bookings
Easily sync multiple calendars and reduce double bookings. Set up individual or team scheduling links to facilitate easy appointments and meetings.
Calendar Syncing
Privacy-focused Calendar sync
OneCal provides a privacy-centric Outlook, iCloud and Google Calendar sync setup that allows customizing how events are replicated across your calendars. Whether you prefer excluding the event titles or displaying specific information, OneCal gives you complete control over the level of detail shown.
Multi-way Calendar Sync Direction
Sync multiple calendars in real-time, effortlessly
With OneCal, you can synchronize multiple Outlook, iCloud and Google Calendars in one go. Just select the calendars you want to keep in sync, and OneCal will keep them in sync in real-time.
Scheduling Links
Share Individual or Collective Scheduling Links
Effortlessly share scheduling links for others to schedule time with you or your team. Say goodbye to tedious back-and-forth communication and confusion.

Unified Calendar View
Manage all Your Calendars in a Unified Calendar View
Manage Outlook, iCloud Calendar, and Google Calendar from a single, unified calendar view. Create, update, and delete meetings, join conference calls, RSVP to events, and more - all through a mobile-friendly, intuitive experience. Available on the Web, App Store and Play Store.

Committed to Privacy & Security
We are committed to providing the best data security and privacy that you and your company can trust. We only request the necessary scopes to perform the services you choose and never sell, store, or analyze any data.

SOC 2 (Type II)
CertifiedSecurity, availability, and confidentiality controls
GDPR
CompliantData protection and privacy rights for every user
No data stored, analyzed or sold
We don't store any calendar event data. We don't analyze any event data. We don't sell or monetize any data.
Secure Access to your Calendars
OneCal connects to your calendars using secure OAuth2 connections such that we never see or store passwords. You can revoke the access at any time.
Minimum Permissions Required
OneCal only requests read and write access to your calendars for the purpose of synchronising your calendars. We don't have access to your files, event attachments, email, or any non-calendar features.
Data encrypted in transit and at rest
The data that we store to perform the app's functionality is encrypted in transit and at rest. Everything runs on AWS inside a private VPC, so it isn't open to the public internet.
Secure and Scalable Infrastructure
OneCal is hosted on AWS, the leading cloud infrastructure provider, and leverages all of AWS's security, privacy, and redundancy features. Our infrastructure is extremely scalable, leaving no room for downtime.
Protected from Attacks
Our application has a web application firewall, we've setup several Distributed Denial of Service (DDoS) Protections, and we do regular vulnerability scanning to make sure the platform stays secure.
Your calendars, connected to everything
OneCal connects with all major calendar providers, video platforms, AI assistants through our MCP server, and 9,000+ other tools via Zapier, so you can simplify your workday and run your business smoothly.
users love onecal
Trusted by thousands of professionals and companies
"I have 9 calendars to manage and it has saved my life. The user interface is intuitive and clean, setup is easy and there's little to no maintenance needed. I didn't read a single support article because it all just makes sense. It offers a variety of options in configuring the sync so that you share only what you want, and the syncs are fast and stay up-to-date in real time. I love the scheduling links and the public calendar and ICS features. It's made it so easy for colleagues and clients to see my actual availability and schedule with me without needing to share my calendars directly."
"OneCal is the only way I found to consistently sync my work (Outlook) and personal (Google) calendars. I tried all the suggested free methods and none were successful. I rely on both calendars and am so pleased I can see them together everywhere I look!"
"I primarily utilize OneCal to keep multiple calendars synced so that different organizations can see my shared schedule. This one tool helps me manage tons of calendars effectively and my coworkers, clients, and companies can all keep track of my schedule in real-time."
"I really appreciate how OneCal solves my need to have all of my calendars synced, so I'm not double booking time on my calendar. It's super easy to set up, and I found the user interface very nice to work with. Once I signed up, I had everything syncing in just a few minutes."
"This has been a true life-saver to have updates syncing in real-time and eliminates the need for a third-party calendar sharing view for me. Was a breeze to set up as well. Thank you for inventing this!"
"OneCal solved ALL calendar issues!
I have 5 different gmail calendars and OneCal is like, 'Not a problem!'
I need multiple booking links - OneCal - 'Not a problem.'
I had an issue (user issue for sure) and A REAL PERSON from OneCal is emailing me with a solution before the end of day.
You simply cannot beat this tool or their amazing support."
"The ability to sync multiple calendars so I can stay on top of my life is really important to me. It made it much easier than other products I tried."
"I'm a consultant. I have 4 different Google Calendar accounts with different companies. The specific issue I needed to solve was that when I put something on one calendar, I needed it to block all of the other calendars. This seamlessly and effortlessly makes that possible. I've used it for 2-3 years now and it's perfect."
"The clean layout and constantly evolving features make it really easy to navigate and great value. It has good integrations with other websites and really quick to load as well. It's made my ROI really high and works great."
"I use OneCal for syncing between three different calendars - day job, my own business, and personal calendar. It solves the big problem of not double booking across different parts of my life. I also appreciate not having to manually cross-check calendars while maintaining privacy on my day job calendar."
"OneCal is the best service I have found for calendar synchronization and management. I have tried other services, and while they work well, none work as quickly and cleanly as OneCal."
"OneCal is easily the best tool for cloning appointments across multiple calendars. I manage so many client calendars that it's way too time-consuming to copy everything manually. With OneCal, I can automatically clone appointments and use my Teams/Office integration so meetings get scheduled appropriately and automatically. It's not the cheapest tool in the industry, but in my experience it's definitely the best. They also have a Discord group with the developers if you ever have UI/UX suggestions or need more direct support."
"I really like OneCal for its seamless experience and the fact it just works. I appreciate how it allows multi-to-multi calendar synchronization, making it possible to synchronize my work, private, and business calendars effectively. After trying multiple calendar tools, OneCal is the first one that actually works for me."
"It's a once-and-done setup, a few minutes to add and sync the calendars and then you never need to touch it again. And reasonable permissions manifest as well. OneCal has been head and shoulders above any other interaction I've seen, with responsive devs eager to explain their design and even implement new features."
"During my search for a meeting scheduling solution, I discovered OneCal. I realized that it could effortlessly address all my calendar-related issues. The setup process was incredibly intuitive, and I can't think of a single drawback to this solution. I had it up and running in just three minutes. "
"I love OneCal for its ability to remove the chaos of scheduling across different time zones and schedules. I appreciate how it organizes both my personal and professional life, preventing me from missing important events like my kid's preschool graduation. The ease of use has significantly reduced my stress."
"Super easy to use, FANTASTIC support, pretty easy to integrate and implement. Use it daily. The calendar sync function alone is worth the price and the UI is excellent."
"I've tried many calendar synchronisation solutions between Google Calendar and Outlook: this one works like a charm. The UI is really nice and the integration is very fast. As a consultant, I need synchronized calendars both in my own company's agenda and in the agenda provided by my customers."
"I use OneCal to manage my bookings across five different businesses, each with its own email address. I like how it cross-checks bookings and blocks off time across all my calendars, which helps avoid any duplicates. It works really well for keeping my schedule organized. I was using Calendly before, but now I use OneCal for my scheduling links, and it syncs well with Google Calendar."
"I work with multiple clients, and it has always been a challenge coordinating availability. OneCal solves this in the simplest way possible: by copying my calendar entries across my calendars, everyone gets to see my actual availability in the system they are already using. OneCal's scheduling links handle availability for anyone outside the organizations I'm already working with. It also lets you select the level of information you share, so one client's information is never shared with another. It's a great system and has already saved me hours of time by not having to reschedule meetings."
"I like that OneCal solves the problem of double bookings for me as a freelancer with multiple email accounts. It books meetings across all my calendars automatically, which is a major benefit. I use OneCal daily and appreciate how easy it is to set up and not have to look back."
- 99.9%
- Sync Success Rate
- 80Million
- Syncs Executed
- 1.2+Billion
- Events Synced
- 150+Years
- Saved Time
All the tools you need to manage your schedule
From an AI assistant and a unified calendar view to mobile apps and AI integrations, OneCal gives you everything to stay on top of your calendars, wherever you are.
- New
AI Assistant
Ask AI to make changes to your calendars, manage calendar syncs and scheduling links, or help with anything OneCal related.
Meet the assistant Unified Calendar View
Manage Google, Outlook and iCloud Calendars in a single view. Create and edit events, RSVP, and join calls without switching apps.
See the calendar viewiOS & Android apps
Manage your calendar syncs, scheduling links and calendars on the go, with the same features as on the web.
Get the appsWorks with your AI tools
Connect Claude, ChatGPT or any MCP client to your calendars through the OneCal MCP server.
Explore the MCP server
Frequently Asked Questions
Ready to sync your Calendars?
Reflecting your availability across multiple calendars is tedious and time-consuming. OneCal was created with a mission to give peace of mind to calendar users.















