DSC_0491.NEF tells you nothing. Worse, in a few years you will have several of them, because camera counters roll over and every body starts at 1.

A naming convention is the cheapest archival decision you will ever make. It costs an hour once, it needs no software to read, and it survives every migration — because unlike a catalogue, a folder of well-named files explains itself to whatever opens it next.

This is about what to put in the name and why. The mechanics of applying it are a separate question, covered at the end.

The four things a filename can carry

Almost every good convention is some arrangement of four elements.

Date — when the photo was taken. Nearly always the most useful single thing, because it is the one fact you can usually recall about a picture.

Subject or project — the shoot, client, location or job. What distinguishes this set from every other set taken that month.

Sequence — a number that makes each name unique within its group and preserves shooting order.

Variant — what this particular file is: the edit, the crop, the web export, the version sent to the client.

You do not need all four. You do need to decide, once, which you are using and in what order — because the order is what determines how the files sort.

Put the date first, and write it as ISO

If you take one thing from this page: write dates as YYYYMMDD or YYYY-MM-DD, and put them at the front.

The reason is mechanical. Filenames sort as text, character by character. 20260731 sorts after 20260730 because the digits compare in order of significance. Write the same date as 31-07-2026 and text sorting groups every 31st of every month together, across all years. Write it as 07-31-2026 and you have grouped every July. Both are chronological nonsense the moment you have more than one month of files.

ISO order is the only form where alphabetical sorting and chronological sorting are the same operation. That is why libraries and archives standardised on it, and it is why the format is worth the small ugliness.

Use the capture date, not the file date. They are different, and the file date is rewritten by ordinary things like copying — this is the single most common way a “dated” archive ends up with wrong dates. How to rename by the date taken covers the distinction.

Characters: be boring on purpose

Filenames travel — to Windows machines, onto web servers, into ZIP files, through backup systems written decades ago. The safe set is small and worth sticking to:

Letters, digits, hyphen, underscore. That is it.
No spaces. They survive most places and become %20 in URLs, break naive scripts, and need quoting in every command line.
Never < > : " / \ | ? * — several are outright illegal on Windows and one is a path separator.
Avoid accents and non-ASCII in filenames, however well your Mac handles them. Encoding differences between systems turn café.jpg into mojibake or a missing file.
Watch total length. Deep folder structures plus long names hit real limits — Archyv caps generated paths at 260 characters, matching the classic Windows limit, and long names are the usual reason.

A useful discipline: use hyphens between elements and underscores within them, or vice versa. Pick one, and a name becomes machine-parseable later.

Sequence numbers: pad them

0001, not 1.

Same reason as dates. Text sorting puts 10 before 2, so an unpadded sequence scrambles the moment you pass nine files. Four digits handles ten thousand frames in a group and costs three characters.

Decide what a number is unique within. Numbering restarted per shoot is usually right — it keeps numbers short and meaningful — and it means the same number appears in different groups. That is fine, as long as the elements before the number differ. Rivera-2026-0001 and Chen-2026-0001 are distinct names; the uniqueness comes from the whole string, not from the counter.

When to encode photographer, camera or location

The test: will this distinguish files that would otherwise collide, or answer a question you will actually ask?

Photographer — yes, if more than one person shoots for the archive. It is the classic case for multi-contributor projects, and it gives each person their own numbering run.
Camera or body — usually no. It answers a question you can already ask of the metadata, and it clutters every name for the rare occasion it matters.
Location — sometimes, for fieldwork or travel archives where place is how you would go looking. Rarely for studio work.
Client — usually better as a folder than a filename.

The general principle: the filename is not a database. Metadata inside the file already holds camera, lens, exposure, GPS and copyright, and it is searchable. The name only needs enough to identify and order the file at a glance, in a window with no software to help it.

Some conventions that work

General purpose 20260731-lofoten-0001.nef — date, subject, sequence. Sorts chronologically, tells you the shoot, unique within it.

Multi-photographer Rivera-2026-0001.cr3 — creator, year, sequence. Each contributor numbers independently.

Client and deliverable 20260731-acme-0042-web.jpg — the variant suffix separates deliverables from masters in the same folder.

Fieldwork 20260731-siteB-0007.orf — date and site, because those are the two axes the data is queried on.

Turning it into something you apply rather than type

A convention only pays if it is applied consistently, and no one types it consistently by hand.

The practical form is a template: a pattern of variables — {yyyy}{mm}{dd}-{seq:4} — that is filled from each file’s own metadata. Build it once, save it, and every future shoot is a single choice rather than a fresh decision. {seq:4} handles the zero-padding, and the elements placed before {seq} determine what the numbering restarts on, which is how the per-shoot or per-photographer grouping above gets implemented.

Two refinements worth knowing when you get there. Case can be enforced across the pattern or per element, so a convention with {CITY}-{artist} renders consistently regardless of how the metadata was typed. And where a value is sometimes missing, a custom variable can chain several sources in priority order and fall back cleanly rather than leaving a hole.

Archyv’s Filename Templates is where a pattern is built and saved; Metadata Renaming applies it to a selection.

Three things not to do

Do not encode information that changes. A rating or a status in the filename means renaming files every time your opinion changes.

Do not rely on the camera’s counter for uniqueness. It rolls over, it resets, and a second body duplicates it.

Do not rename the same files twice with different conventions. Pick one, apply it to the archive, and leave it. Consistency is worth more than optimality, and the second pass is where pairs and sidecars get separated — see RAW+JPEG pairs and sidecars.

Next: apply a convention to an existing archive with renaming from the capture date, or organise the folders to match with sorting photos into dated folders.