Developers
Format JSON, encode and decode, convert bases and colours. The things you look up mid-afternoon with the editor open.
Encoding and counting
3 tools- Base64 encoder and decoder Text to Base64 and back again. With real UTF-8, which is where half the home-made implementations fall over.
- URL encoder and decoder For putting text into an address without breaking it. The difference between encoding a value and encoding a whole URL is the bit that usually goes wrong.
- Character, word and byte counter Characters, words, lines and bytes. Counted properly: an emoji is one character, whatever your editor says.
Formats and data
3 tools- JSON formatter and validator Paste the JSON, pick an indent, done. If something is off we tell you exactly where, and how many keys and how deep it goes.
- JSON to YAML converter Paste the JSON and out comes the YAML. We quote the strings YAML would read as a boolean or a number, which is where nearly every surprise comes from.
- JWT decoder Paste the token and see what is inside. Note: this decodes it, it does not verify it — checking the signature needs the key.
Numbers, time and colour
4 tools- Number base converter Binary, octal, decimal and hex, both ways. With genuinely large integers: 64-bit values come out exact.
- Data size converter Bytes, KB, MB, GB… and KiB, MiB and GiB too. Both systems side by side, which is the only way to see why your 1 TB drive shows 931 GB.
- Unix timestamp converter Timestamp to date and date to timestamp. If the number is in milliseconds we spot it, which is the mistake that wastes the most time.
- HEX, RGB and HSL colour converter Hexadecimal, RGB and HSL, all three ways. Plus the contrast, which is what decides whether readable text fits on top.
Other categories
- Money Compound interest, loans, mortgages and savings goals, with a breakdown of where every figure comes from and a chart of how it evolves.
- Home and energy What your appliances cost to run, what standby really adds up to, and how much material a room actually needs.
- Dates and time Days between dates, ages, working days, deadlines and hours worked. Instant results, no sign-up.
- Cars and travel Real fuel economy, what a trip costs, cost per mile and splitting the bill between everyone in the car.
- Sport Running paces, race-time equivalents, splits and training zones. For running with your head as well as your legs.
- Percentages and maths Discounts, increases, proportions, VAT, averages and grades. Everyday maths, properly explained.