233 in this format. Showing the 48 most recent.
Two cats need three boxes, not two, and each should be one and a half body lengths long — 69 cm for an average adult. The litter figure that follows is larger than most people expect, and knowing why is the useful part.
Marco Bianchi · 6 min read
Length A + half B, width twice C, height D. The width rule is the one that fails people: a dog with 28 cm shoulders needs 56 cm of interior width, and no crate sold by weight rating tells you that.
Marco Bianchi · 6 min read
Thirty thousand stitches at 3.5 mm with fifteen per cent waste is 120.7 metres. The stitch count comes from the file; the average length is an assumption, and doubling it doubles the answer.
Antonio Delgado · 6 min read
Two stitches per 10 cm is the difference between a 50 cm scarf and a 55 cm one. The pattern's cast-on number is only correct for the person who wrote it.
Antonio Delgado · 6 min read
Measured on the resizer itself: Fill is a centre crop with no focal point, and a portrait photo loses 38.9 percent off the top for an X-sized banner. Plus the current published dimensions, each with the date it was checked.
Daniel Okonkwo · 14 min read
The depth follows the job: a bare display, a planted tank whose roots need room, an under-gravel plate. Then comes the number people are unprepared for — substrate is what puts a filled tank past what a piece of furniture can hold. Plus why fine sand compacts and coarse gravel traps waste.
Marco Bianchi · 12 min read
The same 2,000 sq ft lawn at the same 1 lb of nitrogen per 1,000 sq ft takes 40 lb of a 5 percent blend or 4.3 lb of urea. Target nitrogen, not product — and read the bag count as shopping, not spreading.
Marco Bianchi · 12 min read
The same tank needs a 100 W heater in a warm flat and 300 W in an unheated room. The variable is the gap between the water and the room, which most rules of thumb drop entirely. Plus why two smaller heaters beat one big one, and where this calculator's recommendation stops being trustworthy.
Marco Bianchi · 12 min read
A normal medium load in a high-efficiency machine works out at 37 ml. Load size swings that threefold; water hardness only 1.28-fold — and the tool's hardness input carries no units at all. Here are the scales and the conversions it leaves out.
Marco Bianchi · 12 min read
A two-bedroom home comes out at 56 boxes: 14 small, 21 medium, 12 large, 4 wardrobe, 5 dish. The total is the least useful number on the page — here is why the split matters, and what the count leaves out.
Marco Bianchi · 11 min read
Twice the centre distance plus both circumferences is 36 % too long. Here is the real formula, how the two straight runs and the two arcs actually add up, how far the standard approximation drifts, and what to do with a figure that is not a catalogue length.
Marco Bianchi · 15 min read
Numbering a tidy document is trivial. The cases that bite are a page turned sideways, a Letter sheet among A4 ones, a print file with bleed, and a document that already prints its own number. All four were tested: on the first three the number lands exactly where you asked, and the fourth is not detected at all.
Daniel Okonkwo · 14 min read
Numbering starts at 1 and cannot be set to 0, the alignment is spaces rather than zeros, and the remover undoes eight of the eleven separators without touching the indentation. What it still cannot do is tell your numbers from its own.
Daniel Okonkwo · 15 min read
A PDF stores glyphs at coordinates — not lines, not paragraphs, not a reading order. Extraction rebuilds the text from those positions, which is why two columns come out interleaved, a table loses its cells, and a scan gives you nothing at all. Measured by running the tool.
Daniel Okonkwo · 15 min read
One ffmpeg command, no encoder, and a result whose video stream is byte-for-byte the one you started with — verified by checksum. Plus why the file barely shrinks, and the difference between a silent track and no track at all.
Daniel Okonkwo · 11 min read
This is grep for people who do not use grep, with one important difference: the match is a plain substring, so a real regular expression returns an empty box and no error. Every claim here was checked by running the tool.
Daniel Okonkwo · 11 min read
A comma is quoted, a quotation mark is doubled, and a two-line cue keeps both lines — verified byte-identical over three consecutive round trips. What can still change your file is the spreadsheet in the middle.
Daniel Okonkwo · 12 min read
Cue 12 of the English track is not cue 12 of the French one, because translators split and join sentences differently. Two strategies exist for pairing them; this merger uses neither — it interleaves. Here is what that gives you and when it is good enough.
Daniel Okonkwo · 15 min read
Removing the numbers and the timestamps is the easy half. The half that decides whether the transcript is readable is the italic tags, the dialogue dashes, the sound descriptions and the sentences broken across two cues — and this converter leaves every one of them for you.
Daniel Okonkwo · 13 min read
Measure the offset at two points instead of guessing it once. If it is constant, one shift fixes the file. If it grows, it is a frame-rate mismatch — 25 fps against 23.976 drifts 2.5625 seconds every minute — and no shift will ever fix that.
Daniel Okonkwo · 15 min read
Whether a drawn signature is valid is settled elsewhere. What decides whether your document actually gets signed is the order you ask people in, what the audit trail records, and six failure modes that have nothing to do with the law.
Daniel Okonkwo · 18 min read
The smallest thing that is still a table is two lines: a header row and a delimiter row. Here is why the second one is mandatory in GitHub Flavored Markdown, where pipe tables do not exist at all, and what a generator does that hand-typing cannot.
Daniel Okonkwo · 13 min read
A day rate is a price, not an income. Between the invoice and the bank balance sit six separate subtractions, and in three European countries they are ordered differently, capped differently and paid at different times. Here is the whole chain with the 2026 figures that are verifiable and an honest note on the ones that are not.
Camille Laurent · 15 min read
A 13 by 17 ft room is 221 square feet of floor, but carpet comes off a 12 or 15 ft roll, so you buy 255 square feet and bin 34. Here is how to work out the order quantity your supplier will actually invoice.
Marco Bianchi · 8 min read
The last resort when nothing can be compressed further. It works, and it has three sharp edges: the parts are useless on their own, the order is absolute, and the megabyte you set is not the megabyte the limit means.
Daniel Okonkwo · 7 min read
Plain text has no layout, so any converter has to invent one for you. Here is exactly which decisions this one makes — page, margins, font, line breaks — what it does with a tab and a long line, and what you have to add yourself before a note is worth keeping.
Daniel Okonkwo · 19 min read
A 100 percent grade is 45 degrees, not vertical. Percent is rise ÷ run × 100, the angle is the arctangent of the same fraction, and the two are not proportional. Here is the conversion table and the three ways people get it wrong.
Marco Bianchi · 8 min read
Length × width × average depth gives 21,065 gallons for a 32 by 16 ft pool. But average depth only means (shallow + deep) ÷ 2 when the floor slopes evenly, and most pools do not. Here is every shape formula and the correction.
Marco Bianchi · 8 min read
A conventional wet brine is 5 to 6 percent salt by weight of the water and you pull the meat out on a timer. An equilibrium brine is 1 to 2 percent by weight of the meat and water together, and it cannot over-salt. Those are different numbers doing different jobs.
Marco Bianchi · 9 min read
Move in on 18 October at $1,500 a month and you owe $677.42, $700.00 or $690.41 depending on which convention the lease uses. Agree on one before you sign, not after.
Camille Laurent · 6 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
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
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
The quality slider cannot aim at a file size — that is not what it is for. But the limit and the length of your clip already fix the bitrate you are allowed to spend, and one division tells you whether the resolution you are using can possibly fit.
Daniel Okonkwo · 14 min read
A duplex scanner that took one side at a time, a stack fed upside down, a page that came out twice. Reordering is not the same operation as extracting pages, and knowing which one you are doing tells you what happens to everything that is not a page.
Daniel Okonkwo · 8 min read
A landlord wants page 3. An accountant wants January. You need to send those pages and not the eleven others, and there is a trap: the obvious way leaves the removed pages inside the file you send.
Daniel Okonkwo · 11 min read
Nobody owns a scanner any more, so the phone does it. Two things decide whether the result is accepted: how you took the photograph, and what page size it becomes. The second one surprises people, because a photograph turned into a PDF is not A4 unless something makes it A4.
Daniel Okonkwo · 9 min read
A 110 in rise divided by a 7 in target gives 15.7 risers. You round to 16 and divide again, landing on 6 7/8 in. Here is the whole method, and why the building codes do not agree with each other.
Marco Bianchi · 7 min read
Marketplaces, job boards and support forms often accept JPEG and PNG and nothing else. Converting is easy; choosing the resolution is the part that decides whether the recipient can read your document, and it is the part every tool asks you about and nobody explains.
Daniel Okonkwo · 9 min read
A rental file, a loan application, a tender: the requester wants one document, in the order they listed. The merge itself takes seconds. What goes wrong is the ordering, the page sizes and the file that silently loses its signature — all of which are avoidable if you know where they bite.
Daniel Okonkwo · 10 min read
Drop 25 °F and cut the time by about a fifth — then adjust for what the food is and how full the basket is, because those two change the answer more than the rule does.
Marco Bianchi · 7 min read
Set carbs as a fixed gram figure, protein by body weight, and let fat fill what is left. The famous 75 percent fat is an output of that calculation, not an input — and it drops on its own in a deficit.
Sofia Nunes · 5 min read
Add your average cycle length to the first day of your last period. Here is how to measure that length properly, why the estimate has a range rather than a date, and when irregularity is worth a consultation.
Sofia Nunes · 5 min read
The form rejects your file and offers no advice. What works depends entirely on where the megabytes actually are, and for a scanned document the answer is not compression at all — it is resolution. Here is how to tell which case you have in ten seconds.
Daniel Okonkwo · 11 min read
Rent minus charges minus the loan. On an 80 percent mortgage at 3.5 percent over 25 years, a rental only breaks even from about 7.1 percent gross yield — here is the full calculation.
Camille Laurent · 5 min read
A photo file carries coordinates, an exact timestamp, the device and lens, and on some cameras a serial number. Here is what is actually in the block, what stripping does and does not fix, and how to verify it worked.
Daniel Okonkwo · 13 min read
Split a bill and tip evenly across a group. Learn the tip percentage, total, and per-person formulas with a clear worked example so nobody over- or underpays.
Lena Hoffmann · 3 min read
Estimate your retirement age from how many years it takes your savings to reach a target. Learn the growth formula, a worked example, and why the target matters most.
Lena Hoffmann · 4 min read