1. StackPath

Stackpath is one of the most popular CDN service providers for WordPress. Stackpath acquired MaxCDN in 2016. They have larger Worldwide edge locations (50+ edge locations), so it helps you improve the loading speed of your website. It is easy to setup for a WordPress website as you can integrate it with almost all available WordPress cache plugins (W3 total cache, wp rocket plugin will be better).

StackPath Features

1. Serverless Scripting.
2. Custom Rules Engine:- It allows you to create your own EdgeRules.
3.  It comes with a private EdgeSSL certificate for free with their plan. You can also use your own private SSL certificate.
4. Real-time Analytics- It provides full-time reporting ( Bandwidth Usage, Requests, Delivery by Geo/Network, Cache Hit Ratio, Request Hit Ratio, HTTP Status Codes).
5. Stackpath CDN offers unique optimization tools to simplify keeping your content ready to deliver, (GZIP compression, large file segmentation, canonical header insertion).
6. It offers security services like load balancing and DDoS protection, delivery control.
7. RESTful API.

Pricing:- Stackpath CDN Plans start at $10/month. No hidden costs.

2. Cloudflare

Cloudflare is well known and easy to use CDN service provider for WordPress websites. You can use basic Cloudflare features (CDN, SSL certificate, DDOS) for free. Cloudflare blocks suspicious threats and makes your website more secure. It has a large network of globally distributed data centres (A global cloud network that spans over 200 cities in more than 100 countries) and it automatically caches static content. People use Cloudflare services for the purposes of increasing the security and performance of their websites and services.

Cloudflare Features

1. Easy-to-use DNS.
2. Free automated SSL certificates.
3. A global cloud network that spans over 200 cities in more than 100 countries.
4. Load Balancing
5. Minify CSS, JS
6. Rocket loader

** In the free plan it comes with limited features. You need to upgrade your plan to use their premium features. or you can buy separately their individual features like Load balancer, Dedicated SSL Certificate, Image Resizing, Video Streaming etc.

Cloudflare Pricing

• free plan- No charges
• Pro Plan- $ 20 per month
• Business Plan- $ 200 per month

3. KeyCDN

KeyCDN is an easy-to-use, simple and fast content delivery network having more than 25 POPs around the world. It offers the lowest pricing. It supports both origin pull and origin push.

Pros

• Pay-as-you-go
• Free SSL
• HTTP/2 Support
• Real-time Analytics
• DDoS Protection

Cons

• Minimum usage is $4 per month (you will be charged $4 per month atleast).
• Below average response time.