Music and stories between order and noise
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AI music & fiction
AI-powered Eiken study companion you want by your side
Real-time character, line, paragraph count
Japanese era ⇔ AD, age, zodiac
School enrollment & graduation years
Type Japanese in romaji (for overseas users)
Convert Japanese reading to Hangul (name use)
Paste DB/API timestamp, get date. Both ways.
Pick start and end dates to see total days
Monthly calendar of Japanese national holidays and rokuyō (six-day cycle)
Generate secure random passwords with letters, numbers, symbols
Upload a PDF and add form fields
Create QR codes from URL or text instantly
Convert images to WebP, same name with .webp extension
Convert WAV to MP3 in browser, choose bitrate
Basic math, decimals & keyboard (no eval)
Resize by width, keep aspect ratio, batch up to 10
Create campaign URLs with UTM parameters
Generate .htpasswd line from ID & password
See your public IP as soon as you open the page
Paste an IP to see country/region hints
Enter a domain to list nameservers
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