How to scan and digitise paper documents

What to scan first

Trying to scan everything at once wears you out quickly. It is more realistic to start with what you look for often, what would be hard to get again if lost, and what takes up the most space. Warranties, copies of contracts, medical receipts and school paperwork are typical: papers you need urgently once every few years. On the other hand, documents you can request again at any time, or bills you already receive electronically, do not need scanning. Pick one box to begin with and finish it; you will learn what method suits you and how long it really takes.

Choosing a resolution

Resolution is given in dpi, the number of dots per 2.54 cm. Doubling it doubles both width and height, so the file grows roughly fourfold. Matching the setting to the purpose saves space and time compared with always choosing the highest value.

• Ordinary text documents: 300 dpi
• Small print, stamps or signatures that matter: 400 to 600 dpi
• Old photos and drawings: 600 dpi or more
• Notes you will only read on screen: 200 dpi is enough

Colour and file format

A document with only black text can be saved in greyscale, which cuts the file size considerably without hurting readability. Use colour when there are stamps or colour-coded tables. Multi-page documents belong in a single PDF rather than scattered image files, so the page order never gets mixed up. Photos are easier to handle as image files such as JPG or PNG. Setting compression too high in the scanning software blurs the edges of letters and makes text recognition worse later, so keep it at medium or lower for important papers.

Scanning with a phone

Even without a dedicated scanner, the document scanning feature of a phone camera gives perfectly usable results. Taking an ordinary photo, however, keeps shadows and tilt. Placing the paper on a plain, dark background helps the phone find the edges and straighten the page automatically. Even light from above works best, and you should check where the window or ceiling light is so the phone's shadow does not fall on the page. Hold the camera parallel to the paper and zoom in right after shooting to make sure the text is sharp. Thin thermal paper, such as most receipts, fades over time, so scan it soon after you receive it.

Making text searchable

A scanned file is a picture, not text. Optical character recognition, or OCR, adds an invisible text layer over the image so you can search and copy within the file. Many scanning programs and phone features support it. The results do contain errors, though, so documents where numbers or names matter should be checked against the image. A straight, sharp scan is the single biggest factor in getting good recognition.

Naming and folder rules

Name files on the assumption that the person searching later will be you. Putting the date first in year-month-day order means sorting by name also sorts by time. Folders that are too finely divided make it hard to remember where something went; a few broad categories plus years are usually enough.

• Example: 2026-03-15_car-insurance_policy.pdf
• Use the same date, subject, type order for every file
• Split folders broadly: medical, home, car, tax, warranties
• Write the rules down once you have settled on them

Sensitive data and storage

Paperwork is full of things you would not want leaked: national ID numbers, account numbers, addresses. Before sending a scan to someone, cover what they do not need and check that the covering is actually part of the image. In some PDFs a shape placed over text still lets the text underneath be copied out. Do not keep the only copy on one device; back it up separately, and if you put files in a shared folder, check who has access.

Before throwing paper away

Scanning something does not mean every original can go. Documents whose original carries legal weight, such as contracts, IOUs, notarised papers and wills, should be kept, and tax records have retention periods and rules on what counts as valid proof, so check your tax authority's official guidance before disposing of them. Shred anything you discard so personal details cannot be read. For papers you are unsure about, keeping the originals in one box alongside the scans costs a little space but saves a lot of regret.