SSL Certificate Creator
Create self-signed SSL certificates for free
Features
Instantly generate self-signed certificates
Output the certificate, private key, and CSR all at once without a certificate authority
Choose key length and signature method
Supports 2048/4096 bits and four methods such as SHA-256
Set validity from 1 to 10 years
Flexibly set the certificate's expiry to match your testing needs
Download three formats on the spot
Copy and save the private key, certificate, and CSR in separate tabs
How to use
Enter the certificate's issuance details
Enter the target's details such as the common name (domain name), organization name, and country code
Specify key length and signature method
Choose the key size, signature algorithm, and validity period from the dropdowns
Create the certificate with the generate button
Press the generate button to create the certificate, private key, and CSR in the browser
Get the content from each tab
Copy or download from the private key, certificate, and CSR tabs
Use cases
Verify local HTTPS
Quickly prepare a certificate to check HTTPS communication in a development environment
Prepare to build a test environment
Assign a provisional certificate to a staging or internal verification server
Prototype a CSR template in advance
Check the field layout and entered values of a CSR before applying for a formal certificate
As SSL learning material
Use in training and hands-on sessions to learn the structure of certificates, private keys, and CSRs
Basics
What is a Self-Signed Certificate?
A self-signed certificate is an SSL certificate signed by yourself without receiving a signature from a Certificate Authority (CA). While it enables encrypted communication, it is often called a self-signed certificate because it has not undergone third-party identity verification.
Why It Cannot Be Used on Production Sites
Browsers verify certificates by tracing signatures from trusted Certificate Authorities. Self-signed certificates trigger a "This connection is not secure" warning. They should be limited to development, testing environments, or internal systems.
Safety and privacy
Runs entirely in your browser
Your input data is processed only within your browser and is never sent externally.
Processing only in your browser
certificate and key generation is processed entirely within your browser, and input data is not sent to any server.
Communications encrypted with HTTPS
Page loading is also encrypted by TLS, and content cannot be read by third parties.
No transmission to third parties
Input content is not sent to external services such as ad networks or trackers.
No automatic saving of results
the private key you generate and input suggestions are not stored on the server.
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RAKKOTOOLS is free to use!
Available free of charge for individuals and corporations, commercial and non-commercial use alike.No prior permission or usage application is required. Feel free to use it in various situations.
Use in streaming and videos
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Use in schools, work, and events
Can be used in various situations such as classes, team division, internal work, and events.
Introduction on Web, books, and SNS
Feel free to introduce it as a useful tool on web media, books, SNS, and other platforms.
Commercial use
Can be used for commercial purposes such as research, calculation, processing, and conversion in business and production.
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If using in streaming and videos
Link to RAKKOTOOLS in the description, or Mention or display that you are using RAKKOTOOLS in the stream or video.
Credit example for the description
Usage guidelinesYou are free to use it for normal purposes. However, use for purposes that violate laws, infringe on third-party rights, impose significant load on the service, or otherwise interfere with service operation is prohibited.
We do not guarantee the accuracy or completeness of information and calculation results obtained from each tool.
This notice is a translation of the original Japanese text. If there is any discrepancy between the translation and the original, the Japanese original takes precedence.