QR Code Utility
Generate QR codes from any text or URL, and decode QR codes by uploading or pasting an image.
Open tool →JWT Decoder & Encoder
Decode, inspect, and re-sign JSON Web Tokens. Edit header and payload, switch algorithms, and generate HS256 signatures.
Open tool →OAuth2 / OIDC
Build and send OAuth2 / OpenID Connect authorization requests. Supports PKCE, nonce, and state. Exchange authorization codes for tokens.
Open tool →IK Generator
Generate a valid German Institutionskennzeichen (IK) number with correct Luhn checksum, starting with prefix 3001.
Open tool →Group Assignment
Randomly assign training participants into groups. Drag and drop to adjust, reset assignments or everything. State is persisted across sessions.
Punycode Encoder & Decoder
Convert internationalized domain names (IDN) between Unicode and their ASCII-compatible Punycode representation. Detect homograph phishing domains.
Open tool →TOTP Generator
Generate current, previous, and next TOTP codes from an otpauth URI. Includes a countdown timer and code history table.
Open tool →oose Trainingsübersicht
Overview of oose training courses and seminars with scheduling and availability information.
Open tool →Certificate Decoder
Paste or drop a certificate, chain, CSR or CRL in any common format — PEM, DER, PKCS#7, PKCS#12 — and read it as openssl would print it.
Open tool →Timer
Countdown timer with quick presets or a custom duration. Run it fullscreen, pause/resume, and add a minute on the fly without interrupting the countdown.
API Key Vault
Store AI API keys encrypted on the server and let the training VMs fetch them over an authenticated request. Write-only, with an audit log of every access.
Open tool →Certificate Generator
Issue fresh Let’s Encrypt certificates for the training VM domains via DNS challenge, and rebuild the bundle the VMs fetch at boot.
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