The print terms Printicorn uses, explained.

What bleed is

Commercial printers print on sheets larger than the finished piece and cut them down afterwards. The trim line is where the cut happens; the bleed is the zone just outside it, typically 0.125 in (3 mm) wide. Any colour, photo or shape that should touch the finished edge must be extended into this zone.

Bleed is not visible in the finished product. It is deliberately thrown away, which is exactly why it works: the cut can wander slightly in either direction without exposing unprinted paper.

Why it matters

Cutting tolerance on a guillotine or die cutter is commonly ±0.5 to 1 mm, and a stack of sheets can drift more. Without bleed, a full-colour flyer ends up with an uneven hairline of white along one edge — one of the most common reasons print jobs are rejected or reprinted.

• Use bleed whenever any element touches the page edge (backgrounds, photos, colour bars).
• Do not put text or logos in the bleed zone — it will be cut off.
• Keep important content inside the safe area, at least 0.125–0.25 in from the trim.
• Home and office printers usually cannot print to the edge at all; bleed only helps when the sheet is trimmed afterwards.

In Printicorn

Record the bleed your printer asks for under Print intent in the properties panel (0.125 in is the usual default). The page keeps its trim size in the editor and a red dashed outline shows the bleed zone so you can drag backgrounds past the edge. When you export a PDF, choose Include bleed: the PDF page grows by the bleed on every side and the trim box is written into the file so the print shop's software knows where to cut.

What crop marks are

Crop marks (also called trim marks) are pairs of fine lines at each corner of the sheet. Extending the lines mentally across the page gives the trim line. They sit outside the bleed zone, with a small gap, so that the marks themselves never end up inside the finished piece.

Why you would use them

Once bleed is added, the printed sheet no longer shows the true page edge — the artwork simply keeps going. Crop marks restore that information for the cutter. Most commercial printers request PDFs with bleed and crop marks together; some prefer clean PDFs with a trim box instead, so check their specifications.

• Marks are drawn hairline-thin (about 0.25 pt) in registration black.
• They are positioned at the trim corners, offset outward past the bleed.
• Do not add crop marks to files that will be printed on a desktop printer at the final size — they only make sense when the sheet is cut.

In Printicorn

The PDF export dialog has a Crop marks option. Printicorn draws them 0.25 in outside the trim edge, beyond the bleed, and also sets the PDF trim and bleed boxes so imposition software can read the geometry directly.

Trim, bleed and safe area

Think of three nested rectangles. The outer one is the bleed box, slightly larger than the page. The middle one is the trim box — the page size you chose, such as 8.5 × 11 in. The inner one is the safe area, where everything important belongs. Printicorn's page in the editor is the trim size; bleed and crop marks are added only when you export.

Safe area versus margins

Printers usually ask for a safe area of 0.125 to 0.25 in inside the trim. In Printicorn the page margins play that role: the dashed blue rectangle marks the zone to keep important content inside. Backgrounds and photos may run beyond it into the bleed; headlines, body text and logos should not.

What margins do

A margin is a design decision as much as a print requirement. It defines the live area for text columns, tables and images, and it doubles as the safe area for trimming. Most letter-size documents use 0.5 to 1 in; business cards and postcards use 0.125 to 0.25 in; posters viewed from a distance can afford generous margins of 1 to 2 in.

• Keep body text inside the margins; let photos and colour blocks break out to the edge (with bleed) for a bolder look.
• Use equal left and right margins for single sheets; add a larger inside margin for booklets that will be folded or bound.
• Margins are guides, not walls — Printicorn never prevents you from placing something outside them.

In Printicorn

Margins are stored with the document and drawn as a dashed blue rectangle. Snapping uses the margin lines, so dragging a text box near a margin locks it precisely to the edge. Toggle the display under View → Margins.

What a grid is for

Designers use grids to make decisions once instead of hundreds of times. A quarter-inch grid means every element sits at a multiple of 0.25 in, so nothing is off by a hair. Column grids (for example three equal columns with a fixed gutter) organise text in newsletters and brochures; baseline grids keep lines of text in neighbouring columns level.

• Choose a spacing that divides your page evenly — 0.25 in or 5 mm are common.
• Turn snapping on while laying out, then off for fine adjustments.
• The grid is a drawing aid only. It never prints or exports.

In Printicorn

Grid spacing lives in the properties panel under Guides & grid. With Snap to grid enabled, moving or drawing objects rounds their position to the nearest grid line; hold Alt while dragging to bypass snapping temporarily.

Guides versus the grid

The grid is uniform; guides are deliberate. Use guides for the handful of positions that define your layout: column boundaries, the fold of a tri-fold brochure, the top of the body text area. Objects snap to guides just as they snap to the grid, and guides are saved with the document but never printed.

How snapping works

As you drag, Printicorn compares the moving object's left, centre and right (and top, middle, bottom) against candidate positions within a few screen pixels: grid lines, guides, margins, the page centre and edges of other objects. The closest match wins and a pink alignment line appears. Hold Alt to drag freely.

Choosing a size

Pick the size your printer can produce and your audience will see. Standard sizes are cheaper and faster; custom sizes are possible but confirm them with the print shop. When in doubt, design at the final size — never plan to scale a Letter design up to a poster, because photos lose resolution as they grow.

Switching orientation

Changing orientation swaps the page width and height. Objects keep their positions, so check that nothing has fallen off the page afterwards — the Print Quality panel lists objects outside the page.

Points, pixels and inches

One inch is 72 points, 25.4 mm or 96 CSS pixels. Font sizes are always in points. Switching the display unit never changes the document — it only changes how numbers are shown and typed.

The calculation

A 2400 × 3000 pixel photo placed at 8 × 10 in has 300 pixels per inch. Stretch the same photo to 24 × 30 in and each inch now receives only 100 pixels. Nothing about the file changed — the pixels are simply spread thinner. Printicorn always uses the lower of the horizontal and vertical values, because that is the axis that limits sharpness.

• 300+ DPI: excellent for material held in the hand.
• 200–299 DPI: very good; differences are hard to see.
• 150–199 DPI: good, especially for posters.
• 100–149 DPI: usually fine for large-format work viewed from a few feet.
• 72–99 DPI: soft up close; acceptable only at a distance.
• Below 72 DPI: pixels are likely to be visible.

What it does not measure

Effective DPI describes how much data a photo has for its printed size, not how good the photo is. A blurry 300 DPI scan still looks blurry. Text, shapes and SVG artwork are vectors — they have no pixels and stay sharp at any size, so Printicorn never assigns them a DPI warning.

Why distance changes the rules

Average eyesight resolves roughly one arc-minute of detail. At 12 inches that corresponds to about 290 pixels per inch; at 6 feet it is closer to 50; at 100 feet only a handful. Printicorn's guidance model doubles the acuity figure for comfort and caps it at 300 DPI, so a 24 × 36 poster viewed from 6 feet is judged acceptable at around 100 DPI while the same poster held in the hand would want 300.

• Hand-held (business cards, brochures): 1–2 ft.
• Wall posters and menus: 3–6 ft.
• Yard signs and banners: 10–25 ft.
• Billboards: 50–100 ft or more.

It is an estimate

Lighting, contrast, the subject matter and the viewer's eyesight all vary. Treat the recommendation as a well-founded rule of thumb, and ask your printer for a proof when the job is important.

Practical guidance

Use vector formats for logos, icons, diagrams and anything with hard edges or text. Use raster formats for photographs, and source them at the largest pixel size you can. Printicorn marks vector elements as resolution-independent in the Print Quality panel and only computes effective DPI for rasters.

What it shows and does not show

The simulation disables smoothing when the page texture is rendered, so upscaled pixels appear as blocks while text and vector shapes remain crisp. It approximates the information available to the printer; it does not reproduce a specific printer's dot pattern, paper or ink. It is a resolution check, not a colour proof.

What Printicorn checks

Page size, the effective resolution of every raster image at the expected viewing distance, vector elements (marked resolution-independent), whether bleed is configured, objects extending beyond the page, and text smaller than 5 pt. The overall rating — Excellent, Good, Fair or Poor — is driven by the weakest raster image.

What to expect

Printicorn works in RGB, like every browser. Print shops convert to CMYK with a colour profile at their end; the conversion is well understood and usually fine for everyday work. Colour-managed CMYK workflows and ICC profiles are on Printicorn's roadmap.