Provisional workload limits
These conservative starting limits reduce oversized jobs. They are engineering estimates, not measurements of available memory or guarantees that a device can complete a job. Even a small compressed PDF can require substantial memory when opened.
- Up to 20 inputs, 20 MiB per input, and 50 MiB of inputs per draft.
- Up to 200 source pages per PDF and 200 merged or selected output pages per job.
- Up to 50 output PDFs, totaling 50 MiB; up to 52 MiB for a ZIP.
- Images: up to 12 million pixels each, 24 million pixels per draft, and 8192 pixels per dimension.
- PDF source page boxes: at most 14,400 effective points per dimension, including the page's UserUnit scale. Image-sized output pages: at most 6144 points per dimension.
One MiB is 1,048,576 bytes. Limits include the stated boundary. An oversized file-addition batch is rejected in full; existing inputs remain. Other detected violations show an error. Remove inputs, select fewer pages, combine outputs, or prepare smaller originals in another tool. PDFBurrow never silently downsamples or omits output pages.
Originals, decoded images, parsed PDF objects, generated PDFs, and ZIP buffers can coexist. Output-size limits are checked during or after generation; they cannot prevent every allocation failure. Previews are optional, limited to the eight visible items, and paused during generation. Cancel stops the job without changing your originals.
Form filling limits
Fill & sign accepts one standard AcroForm PDF with at most 500 fields and 1,000 page controls, within the shared PDF limits. Only supported visible, printing controls are accepted. A flattened copy must fit the signature editor's 20 MiB input limit before continuing. These additional limits are provisional, not calibrated memory guarantees.
Personal seal limits
Personal seal accepts one PDF of at most 20 MiB, one encrypted key file of at most 16 KiB, and one proof file of at most 16 KiB. It checks PDF headers and exact bytes, not page count or document structure. Page and geometry limits for editing tools do not apply to sealing. Web Crypto operations temporarily lock navigation and cannot be cancelled through the app.
Browser and device coverage
This is an experimental build. Automated Chromium, Firefox, and WebKit coverage is not certification of Chrome, Edge, Safari, or physical iPhone, iPad, and Android devices. Physical-device calibration and current/previous browser-major coverage remain pending. Browser memory pressure can close the tab and lose in-memory work. Keep your originals.