Every reprint looked fine on screen.
That is what preflight is for — the faults you cannot see
A file that opens is not a file that prints. The things that cost a rerun are invisible in a viewer: ink that stops at the knife, a picture that is 96 dpi at the size it was scaled to, a font that was never embedded, white set to overprint. This reads the file itself — the boxes, the resources, the matrix every image is placed with — and then renders each page to answer the one question the structure cannot. Free, in full. No sign-up.
- Free, no account.
- Every check and every report is free from the first open — no sign-up, no credits, no limit on files.
- Nothing is uploaded.
- The file is read in your browser and stays there. A job on its way to press is somebody's unreleased packaging.
- Your printer's figures.
- Bleed, resolution and the finest line are yours to set. A check whose threshold you cannot see is an opinion.
- Measured, not guessed.
- Resolution at the size the image is actually placed, matrices and nested forms included. Line width in millimetres after every transform.
- The check nobody else runs.
- Whether the artwork really carries past the trim — answered by rendering the page, because the structure cannot say.
- A report to send on.
- The findings, the pages they are on, and the thresholds behind them, as a PDF.
What it checks
The faults that survive a look at the screen
Every one of these opens cleanly in a viewer and comes back wrong from the press.
Where the knife falls, and what is past it
- Media, crop, trim, bleed and art boxes, in millimetres
- How much paper stands outside the trim, side by side
- Whether the ink actually carries past the knife — rendered, not assumed
Every picture at the size it is used
- Effective dpi from the placement matrix, not from the file's own size
- Followed through nested forms, where the scale is easy to lose
- Wanted and reprint thresholds, both yours to set
Fonts that will still be there at the RIP
- Embedded, subset, or named and missing
- Type 3 fonts, which are drawings rather than type
- Small text set in more than one ink, which fringes on any press
The inks the job will actually run
- RGB in a four-colour job, named by page
- Every spot ink in the file, listed by its own name
- Output intent — the printing condition the file claims
What it can do
What is read, what is measured, and what is reported
Two readings of the same file: the structure, and the page as it renders.
Geometry
Where the job finishes.
- All five page boxes, per page, in millimetres
- Bleed measured on each side separately
- Whether artwork reaches into the bleed, by rendering
- Mixed finished sizes across one file
- Page rotation, and pages with nothing on them
Content
What is on the pages.
- Effective resolution of every placed image
- Nested form XObjects followed, matrices composed
- Fonts: embedded, subset, Type 3, or missing
- Stroke widths in millimetres after every transform
- Inline images and stencil masks told apart from artwork
Colour
What it prints in.
- Device spaces and ICC spaces, by their component count
- Separation and DeviceN inks, named
- RGB in a CMYK job, or the other way round
- Small text set in more than one ink
- Overprint, including white set to overprint
The report
What you send on.
- Errors, warnings and notes, counted
- Page lists with runs collapsed — 1–8, 10–12
- A page-by-page table: size, bleed, images, worst dpi, fonts, finest line
- The thresholds every check used
- A PDF, in the same house style as the cutting guides
How it works
Drop the file, set your figures, read the list
The file is read in your browser and goes nowhere.
Drop the PDF in
It is parsed on your machine — structure first, then each page is rendered for the checks that need a picture.
Set your rules
Bleed, wanted resolution, the finest line your process holds, and whether the job prints in four inks or for a screen.
Read what came back
Errors first, then what needs a decision, then what is merely worth knowing. Each one names the pages it was found on.
Send the report
A PDF with the findings and the thresholds behind them — which is what ends the argument about whose fault it was.
Where it is used
Before the file leaves, and when it arrives
The same list, read from both ends.
Before you send to print
Five minutes against a week: the faults that cost a rerun are all here, and all of them are cheap to fix while the layout is still open.
Packaging artwork
A dieline job lives or dies on the bleed and the trim box. Both are measured here, per side, per page.
Taking files from a client
A list of what is wrong, with the pages and the figures, is a better answer than “it will not print” — and it arrives in a minute.
Certificates and security work
Hairlines and overprint are the whole trade there, and both are invisible until the sheet comes off the press.
Photo-heavy work
Resolution at the placed size, through every scale and every nested form — which is where a picture quietly becomes 90 dpi.
Archives and reprints
An old file that printed once will not necessarily print again. This says what it depends on before the plates are made.
Questions
What it does, and where it stops
Is my file uploaded anywhere?
No. The PDF is read and rendered in your browser, and the report is written there too. Nothing is sent to a server and nothing is stored — the page would work with the network unplugged after it has loaded.
Is this PDF/X validation?
No, and it does not claim to be. PDF/X compliance is a formal standard with a certification step behind it. This checks the things that actually cost reprints — bleed, resolution, fonts, colour spaces, hairlines, overprint — and tells you the figures rather than issuing a certificate.
Why does it not report total ink coverage?
Because an honest TAC needs the file converted through the printing condition's ICC profile, and that conversion cannot be done faithfully in a browser. A figure worked out any other way would be a guess with a number on it, and a guess with a number on it is worse than no figure at all.
How does it know the artwork does not reach the bleed?
By rendering the page and looking. A strip just inside the trim and a strip just outside it are compared: ink up to the knife and blank paper past it means the artwork was drawn to the finished size. A design with a deliberate white border is not reported — the ink has to stop exactly at the trim for it to count.
What resolution should I ask for?
Three hundred dpi at the placed size suits most offset work; large-format and screen print want far less, and fine art reproduction more. The figure is yours to set, which is why it is a field rather than a rule.
It says a font is not embedded, but it looks fine on my screen.
Because your machine has the font. The RIP will not, and it will substitute one with different widths — the line breaks move and the text runs long, which nobody sees until the proof arrives.
Does it fix anything?
No. It reads and reports; it never writes a changed file. Preflight that quietly repairs is how a job goes to press with a change nobody approved.
How big a file can it handle?
The structure of every page is read whatever the length. The rendering pass — the one that answers the bleed question — is capped at the first forty pages, because rendering is what costs and the answer rarely changes after that.
Why is an encrypted file only a warning?
Because nearly all of them carry an empty owner password and open perfectly well. It is still worth removing: a RIP that honours the permissions flag will refuse the job outright.
Is it really free?
Yes. No account, no credits, no limit on files. It is made by a packaging manufacturer, and it exists so that the artwork reaching our presses is artwork that prints.
Check the file before the plates are made
Bleed, resolution, fonts, colour, hairlines and overprint — measured against your own figures, in your own browser.