Vexil: the flag maker that only makes good flags

01  What Vexil is

Vexil is a free flag maker that takes about fifteen seconds and four choices: a name or a house, three things you stand for, one symbol from a fixed library, and a colour palette. Press Raise my flag and an ensign runs up a mast, unfurls, and hands you the finished flag beside a decoded legend that captions every division, colour and symbol in plain language.

The unusual part is what it refuses to do. Vexil is not a canvas. You cannot drop anything where you like, add text, upload a photo, import a logo, or reach for a fourth colour. It is a rules engine built on the NAVA Good Flag, Bad Flag principles — the five criteria vexillologists actually judge flags by — and it enforces them in code, so a cluttered, lettered, six-colour design is not something this tool can output. What you get instead is flat, symmetrical geometry: a flag a child could redraw from memory, which is what those rules are really testing.

It is free and ad-supported, with no account, email or password anywhere, and the whole thing composes in your browser.

02  The constraint is the product

Because the engine is bounded, it is worth knowing the vocabulary before you open it. Every Vexil flag uses exactly one of six field divisions: a pale down the centre, a fess across the middle, a bend from the upper hoist to the lower fly, a saltire of two crossing diagonals, a canton in the corner nearest the mast, or a triband of three stripes. Every flag uses two or three colours, drawn from nine heraldic tinctures with proper names — Or for gold, Argent for silver-white, Gules for red, Azure for blue, Vert for green, and four more. Every flag carries exactly one charge, from a library of sixteen original abstract shapes. And no Vexil flag has ever carried a letter or a seal.

The colours arrive in six paired families — Ensign, Regalia, Meridian, Nocturne, Sovereign and Celeste — each fixing a colour and a metal together, so contrast is correct by construction: a colour is never placed on another colour, nor a metal on a metal. The engine checks every adjacency it renders and refuses to compose a flag that breaks that rule, which is why every flag reads cleanly at thumbnail size.

The space is finite, and small enough to state honestly. Eighteen values, sixteen charges and six palettes give 4,896 ordered value triples and 470,016 distinct starting points. Run the engine across all of them and 97% come out in two colours; the other 3% earn a third stripe, only ever on a triband, and only in the two families that offer a third colour. The order of your three values matters too: the engine weights the six divisions toward the ones your values favour, so your choices steer the layout without being able to break it.

03  The meaning-key is the other half

A generated flag is a graphic. What turns it into an identity object is the ledger that comes with it. Every Vexil ensign ships with a meaning-key: a short ledger that decodes the design back into the choices you made, so a stranger who has never opened the app can read your flag.

The key works positionally. Your first value is read into the field division, your second into the field colour, your third into the metal. Choose Build, Protect and Lead and the ledger might read: "A fess — a steady horizon held across the middle — what you build, unshaken." Then "Sable — constancy through the dark; here, who you protect." Then "Or — the light you carry; here, who you guide." And finally the charge: "The sun — a new day and warmth given."

Each of the sixteen charges carries its own written meaning — the mullet is a fixed point to steer by, the bridge the distance you close for others, the annulet a promise with no end — and the tinctures do too. Nothing in the ledger is filler: every line traces back to a choice, which is why swapping one value rewrites the whole key rather than one row.

The flag itself is captioned the same way, in a single line: House Marlow's Ensign · a fess, sable & or.

04  What each button really does

Four controls sit under the finished flag.

Reroll keeps your name, values, charge and palette and recomposes the layout from a new seed. The colours are fixed by the family, so what changes is the architecture — a different field division, the charge rescaled to the space it leaves, and, on a triband in Nocturne or Celeste, sometimes an extra stripe. Rerolling one fixed input 200 times visited all six divisions, so this is composition rather than a colour shuffle: if the first result is a flag you nearly like, a few rerolls usually land a stronger one without touching what you chose.

Share mints a link to that exact flag: where the browser offers a share sheet the flag goes out natively, and otherwise the caption and the link land on your clipboard. The link is not a screenshot — it previews the actual ensign, and whoever opens it gets the flag, its meaning-key and a one-tap invitation to make their own. Download is the other half of the artifact: it saves the flag on its mast with the full meaning-key beneath it as a 1080-by-1920 SVG, named after your flag, so it stays sharp at any size and reopens in any vector editor.

One more surface is worth knowing: /today, a plain server-rendered gallery of the ensigns raised that day, with the day's count and a link to each. It is the app's only public list, and on a quiet day it is empty and says so.

05  What it will not do, and who it is for

Three limits are deliberate, and worth knowing in advance.

There is no freehand composition: no dragging a symbol into a corner, no custom shape, no uploaded image. The charge library is fixed at sixteen, all original drawings made for this tool, none of them a real country's emblem, a military badge or a brand mark.

Nothing you type is ever drawn onto the flag. Your name rides on the caption and the ledger only — a design rule rather than a missing feature, since lettering is the most common reason a flag fails at a distance. And the server that mints share links accepts only the curated values, so no free text can reach a flag in the day's gallery at all.

And it is a toy, not a registry. Vexil makes original fictional ensigns for fun — personal flags, worldbuilding, fictional nations, tabletop factions, campaign heraldry. It is not affiliated with any nation and makes no claim to have uncovered your real family's arms. One thing it does keep: your last flag and a running count of how many you have raised, held in your own browser and never sent anywhere. There is no history to sign into and no account to lose.

06  Questions people ask

What are the rules of good flag design?

The standard set is NAVA's Good Flag, Bad Flag: keep it simple enough to be drawn from memory, use meaningful symbolism, use two or three basic colours, avoid lettering and seals, and be distinctive. Vexil enforces all five in code, which is why it can only output a flag that passes them.

How do I make a flag for a fictional country or a D&D faction?

Give it the faction's name, pick three values that describe it, choose one charge and a palette, and raise it. Everything Vexil produces is an original generated design you can download and use for worldbuilding, fictional nations, TTRPG factions and campaign heraldry. If the layout is not quite right, reroll — the colours stay and the composition changes.

Is Vexil an AI flag generator?

No. Nothing here is drawn by a model — the composition is a deterministic rules engine, so the same choices always produce the same flag, and every result obeys the good-flag constraints. AI image tools are optimised to put any image on a flag, which is how you end up with gradients, seals and lettering; Vexil is built the opposite way round.

Is Vexil free, and do I need an account?

It is free and ad-supported. There is no account, no email, no password, no paid tier and nothing to install — it runs in your browser, and the flag composes on your own device.

Can I download or share the flag I make?

Both. Share creates a link that previews the exact ensign, so the person you send it to sees your flag rather than a broken image. Download saves the flag on its mast together with its meaning-key as a 1080 by 1920 SVG file, named after your flag, which stays sharp at any size.

Why can't I add my own symbol or text to the flag?

Because lettering and freehand composition are exactly what the flag-design rules exist to prevent, and a fixed library of original abstract charges is what keeps every Vexil flag legible at a distance and free of anyone else's emblem. The trade is deliberate: fewer things to place, and a result that cannot come out cluttered.

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