If you have a wordpress site try one of these:
http://premium.wpmudev.org/projects/category/plugins/?s=calendar

What you might want to do is look into Google Apps for business. Everyone can add events to the calendar. Of course there are other options. Widgets and the like are a good fit for your website. That is, if you're objective is to allow your company events to be posted to the website and display those events onto the website.

Try Eventbrite if you want to share your events with the rest of the world...

There are several calendar tools that you can find handy to schedule your company events are as follows:
1. Microsoft Outlook: Microsoft Outlook is an email management tool that has an accompanying calendar feature. Users can easily navigate from email discussions to their calendars, quickly recording meeting dates and other obligations.
Outlook lets you share calendars with clients or colleagues, making important dates accessible and visible to those whom you give permission. It is accessible on iOS, Android or Windows devices and can even work on MacBooks. Outlook has gone through many iterations and is currently on Outlook 2016. It offers support for file sharing, keyword suggestions and allows users to create collaborative groups within the platform. It is a hub for efficiency, productivity and smoother business operations.
Features
Email, Calendar, Word, Excel, PowerPoint, Exchange, SharePoint, OneDrive, Skype for Business Microsoft Teams, Yammer.
Integrations
Salesforce, Brainshark, RingCentral, Smartsheet
Pricing
A one-month trial is free for those using Outlook personally. Beyond that, it’s anywhere from $79.99-$119.99 annually, depending on the package. Businesses pay per user, per month. The most basic plan for Office 365 Business is $8.25 per user per month. The Office 365 Business Premium costs $12.50 per user per month. To purchase Office 365 Business Essentials, users pay $5.00 per user per month.
2. Google Calendar: Google Calendar is one of many G Suite tools existing to bring organization and ease of communication to business scheduling. Google Calendar is available to anyone with a Gmail email address. It allows users to create and share events, invite colleagues and prospects to meetings and create shared calendars between teams. This product also offers event reminders, so users are never overlooking an interview or professional phone call. Users can also publish their calendars online for greater accessibility. Google Calendar also integrates with other tools such as Zoom, which is helpful in getting external contacts to call the right number at the right time.
Features
Calendar Scheduling, Invitations, Shared Calendars, Reminders, Room Booking, Sync Calendar with a Phone or Tablet.
Integrations
Zoom, All Google Products, Trello, Zapier and more.
Pricing
G Suite is free for 14 days. Gmail and the accompanying features are free for independent users who do not wish to exceed 30 GB of storage. For the basic plan, cost is $5 per user per month. The business plan costs $10 per user per month. Enterprise edition costs $25 per user per month. There is a team pricing that costs $10 per user per month.
3. Calendar: Calendar is a calendaring tool that syncs machine learning into the app to help users better manage their meetings and overall productivity.
Currently only in beta, the app has smart features that can automatically find the best times for meetings, as well as enterprise team functionality for larger organizations.
Features
Calendar Creation, Follow, Repeat Events, Promotion, Calendar Import, Team Functionality, Machine Learning.
Integrations
Contact vendor for details on integrations.
Pricing
Currently free and in beta.
4. iCal: iCal is the calendar offering by Apple Inc. that runs exclusively on macOS desktops and iOS operating systems. This calendar is, unfortunately, unavailable on Windows computers. Apple Calendar can also be used to share calendars and invites with friends and colleagues. This calendar can give you desktop or mobile notifications with customizable frequency. This allows users to determine what they’re reminded of and when.
Apple Calendar is separate from the iCloud calendar, although the interfaces are the same. Those who have an Apple ID have access to a calendar within iCloud, although the events saved on one calendar are not automatically uploaded to another.
Features
Event Creation, Account Syncing, Reminders, Recurring Events, Color Coding, Invitations
Integrations
Email, Google Calendar, Alexa, Asana and others
Pricing
Apple Calendar is free to those who have Apple devices.
5. Microsoft Exchange: Microsoft Exchange is another hosted email tool that offers calendar and contact features. Although it is also a Microsoft tool, it differs from Outlook. Exchange can be deployed as either an on-premises solution or accessed via the cloud. Organizations can also deploy both types of solutions, if that is what fits their needs.
Exchange has many features that help organizations keep track of overflowing inboxes. It allows you to create collaborative groups that can tackle large volumes of work together. It also makes it easy to co-author and share files, furthering your company’s efficiency.
Features
Multiple Accounts, Calendar Sharing, Email, Data Loss Prevention, Group Inbox, File Sharing, Co-authoring, Conversations, Tasks, Schedules and more.
Integrations
SharePoint, Skype for Business, Word, Excel, PowerPoint, OneDrive for Business, Yammer, Microsoft Teams and more.
Pricing
Exchange Server 2016 is free for a 180-day trial. Pricing after that varies from $4.00 per user per month to $12.50 per user per month.
6. Time Trade: Time Trade is an online appointment scheduling software. It has editions for individuals, businesses, and enterprises. The platform is designed to help you capture customers as they are most interested in your product or organization and get them onboard.
Features
Appointment Scheduling, Queue Management, Reporting, CRM Integration, Appointment Routing, Central Administration, Pooled Resource Scheduling.
Integrations
Salesforce and other CRM solutions.
Pricing
Product offers a 15-day trial. Beyond that, users pay $49 per person per year for individual use. Business and business plus plans cost $149-$300 per year. Scheduler for Salesforce costs $350 per year. The enterprise edition pricing is available upon request.
7. IBM Domino: IBM Domino is an email client for enterprise organizations. Its homepage says it integrates social collaboration, messaging and business applications into a single workspace. It has features for emailing, calendaring and managing contacts. IBM Notes is a cohesive collaboration tool for tasks and projects, and calendaring is only a single part of that.
Features
Email, Calendar, Contact Management, IBM Connections Files and Connections Profiles, Instant Messaging with IBM Sametime.
Integrations
Live Text, Open Social, IBM Sametime.
Pricing
IBM Notes offers a free 90-day trial for users to decipher whether it is the right tool. Users should contact the vendor for additional pricing information.
8. Silverline Calendar: Silverline Calendar is a tool that allows you to create and customize your own calendars. It allows you to record events, opportunities, campaigns, tasks, and custom objects. It has a drag-and-drop interface where events can be cloned and set to recur. Silverline Calendar is a custom calendar app for Salesforce. It exists to help sales teams and professionals remain in control of their calendar and scheduling. It is even utilized within the Salesforce corporation. It has robust search features and supports group calendaring.
Features
Toggle Between Calendars, Dynamic Search, Switch Views, Shared Calendars, Create/Edit Easily, Chatter Integrated.
Integrations
Chatter
Pricing
This product offers a 15-day free trial. Beyond that, it’s $10 per user per month.
Appointment.one: Appointment.one is an appointment or meeting scheduling tool that boasts its simplicity. It can be used for one-on-one conversations or book time for an entire team to meet. It also can be configured to show people’s availability. This is a useful tool for client booking, as it allows them to see open times to meet with your employees. Attendees enter their information into a form, which in turn creates a calendar event. This helps the meeting leader understand who all to expect on a call or in a meeting.
Features
Teams, Groups, Multi-Calendar, Self-Scheduling, Create Real Appointments.
Integrations
Common CRMs, Trello, or other built-in integrations.
Pricing
This product is free for basic users. The standard plan is $9.95 a month, and the enterprise plan is $14.95 per month.
9. Axigen: Axigen is a business email and communication tool with calendaring capabilities. It allows users to schedule meetings and organize their workflows. Calendars can be shared between users, and the tool can book conference rooms for efficient meetings. Calendars can be personal or public, depending on their unique nature. Users can also take notes within the calendar tool regarding meeting partners or reminding Bob to bring the forms from HR.
Features
Schedule Meetings and Organize Tasks Share and Delegate.
Integrations
Integrations are not readily available.
Pricing
Axigen is free for five or fewer users. Beyond that, users pay annually. The Business Core plan with up to 10 users costs $543 for the first year. The Business Complete Plan for up to 10 users is $630 for the first year.
10. CalendarX: CalendarX is a calendaring tool that facilitates audience communication. It allows administrators to update a calendar of events so a public audience can remain up to date. Administrators can generate an unlimited number of calendars and give website visitors the opportunity to follow them. This type of calendaring tool proves useful to towns trying to keep residents updated on events, or companies that want customers to come out and celebrate occasions. Events can be recurring or one-time. Audiences can opt to receive notifications, so they never miss a change.
Features
Calendar Creation, Follow, Repeat Events, Promotion, Calendar Import, Customization, Interactive Data and Analytics.
Integrations
Contact vendor for details on integrations.
Pricing
This tool is free for hobbyists. Beyond that, users should visit the pricing page for information.
Besides if you do have any questions give me a call: https://clarity.fm/joy-brotonath