The rule that decides whether a checklist works
Five to nine items per block. That is the whole thing, and it is not an opinion.
Checklists as a discipline start with the crash of the Boeing Model 299 in 1935: an aircraft so complicated that a crew of experts forgot one step. The response was not more training, it was a card short enough to be read. Every study since, up to and including the WHO surgical safety checklist, has landed on the same finding.
Past roughly nine items in one block, people stop reading and start ticking. A 40 item list gets signed off in eleven seconds and catches nothing, and the person doing it is not being lazy: they are responding sensibly to a document that has stopped carrying information.
So break it into sections. A heading gives a natural place to pause, and it is what makes a long checklist survivable rather than theatrical.
Read-do and do-confirm are different tools
These get mixed up constantly, and getting it wrong is why checklists get resented.
Read-do
Read the item, then do it. Right for something unfamiliar, and right for an emergency, because in an emergency nobody is thinking clearly and the order matters. Written as instructions, in sequence, and held in the hand while the work happens.
Do-confirm
Do the job the way you always do it, then run the list to confirm nothing was missed. Right for experienced people doing routine work, which is nearly every checklist on a site.
Hand a time-served fitter a read-do list for a job they have done a thousand times and you have told them you think they need instructions. They will resent it, and they will be right to. The same content written as a do-confirm list gets used.
An item that cannot fail is not a check
This is the most common fault in checklists people write themselves. Compare:
- "Check guards". You looked. Tick. It cannot fail.
- "Guards fitted to both grinders". Either they are or they are not, and the tick means something.
The test is whether you could be wrong. Anything starting "check", "ensure" or "verify" with nothing after it is a ritual rather than a check, and the tool flags them, because they are the items that make the whole sheet feel like paperwork.
One more: if an item contains the word "and", it is usually two checks, and two checks cannot be half ticked. Split them.
Paper is the output
Site checklists, kitchen checklists, handover checklists: they get printed, ticked with a pen and photographed. A tool that only produces a web page has missed what the thing is for.
- The tick box is big enough to use with a pen on a clipboard.
- There is an option for a ruled space beside each item, for the note about why one failed.
- A section will not break across a page, which matters more than it sounds: half a section at the bottom of page one is exactly how items get missed.
Sending it to somebody
Copy a link. The whole checklist is packed into the part of the address after the hash, and a browser never sends that part to a server, so the content genuinely does not leave the machine even though the link works for whoever you send it to.
No account at either end, nothing stored here, and nothing to expire. Everything runs on your own device.
Common questions
How many items should a checklist have?
Five to nine in any one block, with a heading on each block. It is the most consistent finding in the whole subject, from aviation in the 1930s through to the WHO surgical safety checklist. Past about nine, people stop reading and start ticking, which is how a 40 item list gets signed off in eleven seconds and catches nothing.
What is the difference between read-do and do-confirm?
Read-do means you read each item and then do it, which suits something unfamiliar or an emergency where nobody is thinking clearly. Do-confirm means you do the job the way you always do and then run the list to confirm nothing was missed, which suits experienced people doing routine work. Nearly every checklist on a building site should be do-confirm, and handing an experienced fitter a read-do list is the fastest way to get the whole idea resented.
Why does it say some of my items are too vague?
Because an item has to be something a person can be right or wrong about. "Check guards" cannot fail: you looked, so you tick it. "Guards fitted to both grinders" can fail, and that is the difference between a check and a ritual. If an item cannot be wrong, it is not doing anything.
Can I print it?
Yes, and it is designed for that first. The tick box is big enough to use with a pen on a clipboard, there is an option for a ruled space to write beside each item, and a section will not break across a page. That last one matters more than it sounds: half a section at the bottom of page one is how items get missed.
How do I send it to somebody?
Copy a link. The whole checklist is packed into the part of the address after the hash, which a browser never sends to a server, so nothing is stored anywhere and there is no account at either end. Anybody opening the link gets the checklist ready to print.
Is there a length at which a link stops working?
A very long checklist makes a very long link, and some systems truncate an address past about 2,000 characters. For a normal checklist of a few sections you will not get near it. If you are building something enormous, print it or copy the text instead.
Why does it keep asking for a signature line?
Because a checklist with nobody named on it is a piece of paper rather than a record. The signature is the first thing anybody asks for afterwards, and adding it later is impossible.
Is my checklist stored anywhere?
No. It exists in your browser and in the link if you copy one. There is no account, nothing is uploaded, and closing the tab without copying the link or printing loses it.