Practical guides, how-tos and comparisons to get the most out of our free online tools.
One of these formats stores the samples, one stores the same samples packed smaller, and one stores a guess about what you would have heard. Which conversions between them are free, which are merely expensive, and which are one-way doors — with the arithmetic for each.
Daniel Okonkwo · 15 min read
Strip tags before decoding entities, trim before deduplicating, collapse whitespace last. Three orderings run in Node, a nine-step pipeline in the right sequence, and the invisible characters — U+00A0, U+200B, U+FEFF — that survive every naive cleanup.
Daniel Okonkwo · 14 min read
Flour is 100 percent and everything else is measured against it. That one convention lets the same recipe scale from a single loaf to a bakery batch without a single new calculation — and yes, the percentages are supposed to add up to more than 100.
Marco Bianchi · 7 min read
There is no honest single figure for a renovation. Build it up by work type, accept that labour is the biggest and least predictable line, and hold 10 to 20 percent back for what the survey could not see.
Camille Laurent · 6 min read
The soundtrack inside your video has already been through a lossy encoder once. Whether extracting it costs you a second pass depends entirely on which of the three buttons you press — and "extract to MP3", the one everybody reaches for, is the one that costs.
Daniel Okonkwo · 15 min read
A GIF has no real video compression: every frame is a whole picture, capped at 256 colours. That gives you an arithmetic you can do in your head — width times height times frames — and three levers to pull when the upload box says the file is too big.
Daniel Okonkwo · 14 min read
Percent-encoding is decided per URL component, which is the whole source of the confusion. A slash is legal in a path and must be escaped in a query value; a space is %20 in a path and may be + in a form body. Here are the exact RFC 3986 sets, the three JavaScript functions that disagree, and the traps.
Daniel Okonkwo · 16 min read
The division takes a second; the trap is the area. A listing that looks 6 percent cheaper per square foot turns out to be 17 percent more expensive once both are measured the same way.
Camille Laurent · 6 min read
Loan divided by the lower of price and appraised value. The bands at 80, 90 and 95 percent are where pricing steps — and a valuation that comes in low moves you across one without you touching the deposit.
Camille Laurent · 5 min read
Going from 1080p to 720p does not halve the picture: it removes 56 % of the pixels, and it removes rather less than that of the file. Here is the ladder with real pixel counts, honest bitrates and what three minutes weighs at each rung — plus the reason a low-bitrate source barely shrinks at all.
Daniel Okonkwo · 11 min read
Entropy measures the process that produced a password, not the characters in it. H = L x log2(R) is only true when every character was chosen at random — which is exactly why a meter scoring a human-invented password on its character classes is measuring the wrong thing.
Daniel Okonkwo · 16 min read
A JWT is signed, not encrypted. Anyone holding the token can decode the payload and read every claim in it. Here is a real token, decoded without any key, plus the three attacks the signature is supposed to stop and the one problem it cannot solve.
Daniel Okonkwo · 16 min read