About Pocketool Lab
Pocketool Lab collects the free online tools Casper builds, together with notes on the software development, AI assisted work and design behind them. Every tool is built on the same three principles: free, ready to use, and respectful of your privacy.
Your tool pocket
The idea is a pocket with a handful of genuinely useful things in it. Work out a number, tidy up some text, look up an address, or practise speaking English. Whatever brought you here, the hope is that something in the pocket turns out to be the right size for the job.
The otter reaching into the orange pocket is the mascot of this site. It stands for curiosity, quick thinking, and being ready to help. Tools get added over time and existing ones keep changing based on what people report, so each small helper gets clearer and easier to use.
Site colours
The site uses bright, warm colours while keeping text contrast high:
| Colour | Hex | Used for |
|---|---|---|
| Vibrant orange | #FF6A3D | Logo, buttons and important cues |
| Cream white | #FFFBF6 | Page background and open space |
| Deep cocoa | #352B26 | Text, outlines and weight |
| Misty blue | #D7ECF0 | Supporting blocks and small details |
About me
I am Casper, a software engineer who came from visual design, and a co-founder of HexSchool. My degree is in visual design and I started out doing Flash and print work. When responsive web design took off I fell into programming, and through constant self study and sharing what I learned in the community, I gradually moved from designer to engineer.
That route through design is why I am comfortable explaining abstract programming ideas with visuals and everyday comparisons. I believe making a mistake early costs far less than making it later, which is also why I started speaking publicly about technology early, first at local community meetups and later through online courses and teaching.
What I work with
JavaScript, Vue.js, CSS, Sass and SCSS, and responsive web design, along with Node.js on the back end, Docker, deployment, and in recent years AI assisted development as part of everyday engineering practice.
Background
- Co-founder of HexSchool
- Software engineer, previously a visual designer, and an instructor
- Instructor for HexSchool online courses, including practical Vue.js and JavaScript interview preparation
- Participant in the iThome Ironman contest for several consecutive years, writing technical articles 30 days in a row each time
- Author of the personal technical blog Casper Blog
The tools I make
- Compound Interest Calculator, money projections
- Kaomoji, text faces and symbols
- QR Code Studio, QR code generator
- Taiwan ZIP Code Lookup, Taiwan postal codes
- Taiwan Money Calculator, five dimension financial ranking
- Speak Cards English Practice, speaking practice with AI
- Spinning Top Arena, online battles in the browser
Get in touch
Suggestions and collaboration are welcome. The contact page has the channels to reach me. If any of these tools helped, passing them on to someone who needs them is appreciated.
For how data is handled on this site, see the Privacy Policy.