About Make in Bulk

Make in Bulk is a free mail-merge tool for PDFs. You bring a PDF template (a certificate, a letter, a badge or a fillable form) and a spreadsheet, and it produces a personalised copy for every row: as separate, individually named files or as one document ready to print.

Why it exists

Personalising the same document for a list of people is one of the most common office jobs there is: certificates after a training day, thank-you letters after a fundraiser, the same form filled in for every new starter. The usual options are fiddly. Word’s mail merge doesn’t work on a finished PDF design. Desktop PDF editors that can do it are expensive. Many online tools ask you to create an account, add a watermark unless you pay, or require you to upload a spreadsheet full of names, addresses and email addresses to a server you know nothing about.

Make in Bulk takes a different approach: the whole job runs inside your web browser. There is nothing to install, nothing to sign up for, and your files never leave your device.

How it works

When you add a PDF, your browser reads it and draws the pages on screen so you can place text on them. When you add a spreadsheet, your browser parses it and shows a preview. When you press Generate, your browser builds each PDF in memory and hands you the finished file to save. The website itself is a set of static files; there is no server-side code that could receive your documents even if we wanted it to.

The only thing the tool remembers is your layout (where the text boxes are and what they say), which it saves in your browser’s local storage so that a refresh doesn’t lose your work. It never stores the rows of your spreadsheet. You can clear everything at any time with the “Start over” button.

How it’s funded

The site is supported by adverts from Google AdSense. Ads appear around the tool and the guides, never inside the working area and never disguised as buttons or download links. There is no premium version, no feature held back for paying users and no watermark. We don’t sell data; there isn’t any data about your documents to sell. The privacy policy explains how advertising cookies work and how to opt out of personalised ads.

Built on open-source software

The heavy lifting is done by excellent open-source libraries, loaded from the jsDelivr CDN at exact, pinned versions:

• pdf-lib (MIT licence) creates and edits the PDFs, embeds fonts and fills forms.
• @pdf-lib/fontkit (MIT licence) reads the TrueType and OpenType fonts you add.
• PDF.js by Mozilla (Apache 2.0 licence) draws PDF pages on screen for the editor and the exact preview.
• SheetJS Community Edition (Apache 2.0 licence) reads Excel and OpenDocument spreadsheets.
• JSZip (MIT licence) packs separate PDFs into a single ZIP download.

CSV parsing, placeholder handling, text layout and file naming are written specifically for this site.

Limitations we’re honest about

• The tool adds text, not images, so per-person photos, QR codes and barcodes aren’t supported yet.
• Text boxes don’t flow from one page to the next.
• Right-to-left and shaped scripts (Arabic, Hebrew, Devanagari and similar) aren’t laid out correctly yet.
• Adobe XFA (“LiveCycle”) forms can’t be filled in a browser, though you can place text boxes on them.
• Very large batches are limited by your device’s memory.

Contact

Found a bug, have a feature request or a PDF that doesn’t behave? Email hello@makeinbulk.com and tell us which browser you use and what you did. Please don’t send us documents containing other people’s personal information; a description or a made-up example is enough.