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244 in this format. Showing the 48 most recent.

Latest guides

October 15, 2026
How-to · Everyday

Predicting Tides From a Single Known High Water

One high water and the 12 h 25 min lunar interval give you every high and low for days. The rule of twelfths then tells you how much water has moved at any point in between — and both stop being reliable at exactly the same place.

Lena Hoffmann · 6 min read

September 16, 2026
How-to · Files

One File per Tab, and What a Split Leaves Behind

Splitting a workbook writes one .xlsx per sheet, named after the tab. It carries the values across and not the formulas — which is the right default when the point is to send one department its own tab.

Daniel Okonkwo · 4 min read

September 14, 2026
How-to · Files

Merging Workbooks: One Sheet Each, or One Table for All

Twelve monthly reports can become twelve tabs or one table of twelve months. Only the second can be sorted and summed in one go — and it is the one where the header rows need handling.

Daniel Okonkwo · 4 min read

September 10, 2026
How-to · Everyday

Binding a Quilt: Strips, Bias and the Fabric to Buy

A 150 × 200 cm quilt has a 725 cm perimeter once you allow for the join, which is seven strips off a 110 cm bolt and six off a 140 cm one. The strip width you choose sets the fabric, and the corners set whether it lies flat.

Antonio Delgado · 6 min read

September 8, 2026
How-to · Files

You Do Not Have to Rename Your Columns to English

The header row is matched in six languages, so prénom, apellidos, Vorname and cognome are all understood. One header is genuinely ambiguous — nom — and it is settled by the column next to it.

Daniel Okonkwo · 4 min read

How-to · Files

Splitting a Mail Archive Into One File per Message

An .mbox is one enormous file your operating system cannot search. Turn it into .eml files and every message becomes something your machine indexes, your mail client opens and you can delete one at a time.

Daniel Okonkwo · 3 min read

September 7, 2026
How-to · Files

Opening an .eml File Without Telling the Sender

A saved message is a text file you can read anywhere. The catch is that opening it in something that loads remote images announces the moment you did — which is what a tracking pixel is for.

Daniel Okonkwo · 5 min read

September 4, 2026
How-to · Everyday

Hay by Body Weight: Flakes, Bales and a Whole Winter

A 500 kg horse at maintenance eats 10 kg of hay a day — four and a third flakes, fifteen bales a month, ninety bales across a hundred-and-eighty-day winter. The activity percentage moves that by nearly half.

Marco Bianchi · 5 min read

How-to · Everyday

The 80/10/5/5 Raw Ration, Worked From Body Weight

A 25 kg dog at maintenance eats 625 g a day: 500 g muscle meat, 63 g edible bone, 31 g liver and 31 g other organ. The percentage you pick is worth more than every other input combined — growth is exactly double maintenance.

Marco Bianchi · 5 min read

September 3, 2026
How-to · Everyday

n + 1 Litter Boxes, and What the Litter Actually Costs

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

How-to · Everyday

The IATA Crate Formula an Airline Measures at Check-In

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

September 2, 2026
How-to · Everyday

Estimating Embroidery Thread From a Stitch Count

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

August 31, 2026
How-to · Everyday

Cast On From Your Gauge, Not From the Pattern

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

August 27, 2026
How-to · Images

Resizing an Image for Each Network Without Distorting It

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

August 20, 2026
How-to · Everyday

How Much Substrate Does an Aquarium Need? Depth, Weight and Grain Size

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

August 19, 2026
How-to · Everyday

What Wattage of Heater Does an Aquarium Need? Volume Is Only Half the Answer

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

August 18, 2026
How-to · Everyday

How Much Laundry Detergent to Use: Load Size First, Water Hardness Second

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

August 14, 2026
August 13, 2026
How-to · Files

Adding Page Numbers to a PDF When the Pages Are Rotated or Mixed Sizes

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

August 12, 2026
How-to · Text

Numbering the Lines of a Text for a Review with Several People

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

August 11, 2026
How-to · Files

Extracting the Text from a PDF, and What the Layout Does to It

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

How-to · Files

Removing the Sound From a Video Without Touching the Picture

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

August 7, 2026
How-to · Text

Filtering Lines by a Pattern Without a Command Line

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

August 5, 2026
How-to · Web

SRT to Text: Getting a Clean Transcript Out of Subtitles

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

August 4, 2026
How-to · Files

Sending a Document for Signature: the Workflow, Not the Law

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

July 30, 2026
How-to · Web

Building a Markdown Table From Scratch, Without Counting Dashes by Hand

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

July 20, 2026
How-to · Business

From a Day Rate to Money in the Bank: the Whole Chain in France, Germany and Italy

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

July 14, 2026
July 13, 2026
How-to · Files

Splitting a File That Is Too Big to Send

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

How-to · Files

Turning Notes into a PDF Worth Archiving

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

July 10, 2026
July 8, 2026
How-to · Text

Cleaning Messy Text: The Order of Operations That Actually Matters

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

July 7, 2026
How-to · Files

Getting the Audio Out of a Video Without a Second Generation of Loss

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

July 3, 2026
How-to · Files

Getting a Video Under an Upload Limit Without Guessing

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

July 2, 2026
How-to · Files

Putting a Scanned Document Back in the Order It Was Printed

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

June 30, 2026
How-to · Files

Photographing a Document and Getting a PDF That Is Accepted

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