How to Upload Files Larger Than 300 MB to Cloudflare R2 Using CyberDuck
If you use Cloudflare R2 for object storage, you may want to upload files that are larger than 300 MB. The Cloudflare Dashboard doesn't allow this, however you can use any third party app that is compatible with the Amazon S3 API. CyberDuck works for me, so here's the steps for how to use it with R2 to upload files larger than 300 MB.
Generating a Cloudflare R2 Token
Visit CyberDuck.io/download to download CyberDuck and then open the installer and follow the on screen instructions.
Go to https://dash.cloudflare.com/?to=/:account/r2/api-tokens/create to open the R2 API Key Creation Page.
Under "Token Name" enter a name so you know what the API Token is for. I'll call mine "R2 Token For CyberDuck".
Under "Permissions" choose either Object Read & Write or Admin Read & Write.
Under "Specify Buckets", choose whether you want all buckets to be accessible in CyberDuck or just specific ones.
Under "TTL" choose how long you want the API Token to be valid for.
Optionally configure "Client IP Address Filtering".
Click "Create API Token".
Note down your Access Key ID and Secret Access Key.
Connecting to R2 Using CyberDuck
Now you have created your API Token, which you can find details for at https://dash.cloudflare.com/?to=/:account/r2/api-tokens, you can use this to connect to R2 using CyberDuck.
Open CyberDuck and go to File → Open Connection (Command/Control + O).
In the first dropdown select "Amazon S3". If you don't see this option, go to https://docs.cyberduck.io/protocols/s3/cloudflare/ or https://profiles.cyberduck.io/Cloudflare R2 Storage (S3).cyberduckprofile to download the CyberDuck R2 profile and open it.
Go to https://dash.cloudflare.com/?to=/:account/r2/overview and choose any of your buckets.
Click the Copy button just below the search box.
Paste what you just copied into the "Server URL" field in Cyberduck.
Remove the bucket name from the end of the URL (unless you only want to access that specific bucket).
Enter your Access Key ID and Secret Key ID from step 9 of the previous section.
Click connect. Done!