A PDF looks like a document, but it can behave in two very different ways. Some PDFs contain real text that you can select, copy and search. Others are nothing more than pictures of pages, produced by a scanner or a phone camera, with no text inside at all. The way you translate the file depends entirely on which kind you have. Get this wrong, and you spend an hour fighting a file that was never going to cooperate.
This guide explains how to tell the two kinds of PDF apart, how to translate a scanned PDF page by page using our image to English tool, how to get clean results from a scan and how to keep a long document organized. It also explains what image translation cannot do, so you know when to look for another solution.
Step one: find out what kind of PDF you have
Open the file and try a few simple tests.
| Test | If it works | If it does not |
|---|---|---|
| Drag your cursor across a sentence | The text highlights: it is a text PDF | You select a whole box or nothing: it is a scanned image |
| Press the search shortcut (Ctrl+F or Cmd+F) and type a word you can see | The word is found: it is a text PDF | Nothing found: it is a scanned image |
| Copy a paragraph and paste it into a note | Readable text appears: text PDF | Nothing or a picture: scanned image |
Some PDFs are a mix: a scanned page with a hidden text layer added by software. These usually behave as text PDFs, but the hidden text can contain errors. If copied text looks garbled, treat the file as a scan.
If it is a text PDF: use the simpler route
When you can select the text, you do not need image translation. Copy the text, and paste it into a translator, or use your browser or your document software’s own translation features. Copied text is always more accurate than text recognized from a picture, because no recognition step is involved. Reserve image translation for pages that are genuinely pictures.
If it is a scanned PDF: turn pages into images
Our tool translates pictures, so each page must become an image. There are several ways to do that.
- Screenshot the page. Open the PDF at a comfortable zoom and capture the page. This is the quickest method. On a computer, you can paste the screenshot straight into the translator with Ctrl+V or Cmd+V. See how to translate an image on a PC or Mac.
- Export pages as images. Many PDF viewers can export a page as a JPG or PNG file. This gives you a higher resolution than a screenshot.
- Photograph a printed page. If you only have paper, follow the tips in our photo settings guide.
For long documents, plan to work page by page. The free tool processes one image at a time. A batch feature is planned for paid plans, which you can read about on our pricing page.
Getting a clean image from a PDF page
Zoom before you capture
A page shown at a small zoom has small letters. Zoom in so that the text is comfortable to read, then capture one section at a time if the page is long.
Capture one column at a time
Two column layouts confuse reading order. Crop and translate each column separately.
Skip the margins
Crop out headers, footers, page numbers and decorative borders, unless you need them.
Check the scan quality
If the original scan is faint, tilted or low resolution, the result will be affected. As a rough guide, a scan at about 300 dots per inch is a good standard for text. Lower resolutions lose detail, and very high ones create large files without much benefit.
Step by step: translate a scanned page
- Open the PDF, and zoom until the text is clear.
- Capture the page, or one column, as an image.
- Open the translator and add the image.
- Choose the document’s language and the language you want.
- Press Translate.
- Compare the recognized text with the page, especially numbers, dates and names.
- Copy the result into a working document, labeled with the page number.
A workflow for long documents
A twenty page document is manageable if you set up a system.
- Create a working file. Open a document or a note with a heading for each page.
- Keep the translator open. The reader stays loaded, so later pages are faster.
- Translate in order. Paste each translation under its heading.
- Mark doubts. Highlight any word, number or sentence you are unsure about.
- Review at the end. Read the whole thing for sense, and check the marked items against the pages.
- Keep the originals. Store the original PDF with your translation.
If the document includes tables, translate them one at a time and rebuild them yourself, since layout is not preserved.
What you will not get
- The original layout. The tool returns plain text. Columns, tables, fonts and images are not recreated.
- A translated PDF. You get text to copy, not a finished file in the same design.
- Stamps, signatures and handwriting. These are usually not read, or are read poorly.
- Charts and diagrams. Only their text labels are recognized.
- A certified translation. Authorities may require a professional.
If you need a translated document in the original layout, a professional translation service or document translation software is a better fit.
Specific kinds of scanned documents
Contracts and legal papers
Use image translation to understand the outline only. Have a qualified translator and a lawyer review anything you will sign or submit. See translating business documents.
Academic papers and books
Scanned books often have curved pages, shadows near the spine and small print. Translate in small sections, and see our workflow for study materials. Be mindful of copyright when you share anything.
Forms and certificates
Forms combine printed text, boxes and handwriting. Translate the printed prompts, and fill the form in the original language, with help if necessary. Certificates often need a certified translation.
Old documents
Old letters and archives use faded ink, unusual fonts and spelling that changed over time. Expect poor results, and consider asking an expert. See also translating handwritten notes.
Invoices and statements
Check amounts and dates carefully, and verify any payment details through another channel. See translating receipts and invoices.
Where translations go wrong
| Issue | What you will notice | What to do |
|---|---|---|
| Low resolution scan | Many small errors | Find or make a better scan |
| Tilted pages | Lines out of order or broken words | Rotate the image so lines are level |
| Columns and tables | Mixed up text | Crop one column or cell group at a time |
| Stamps over text | Missing words under the stamp | Read those parts yourself |
| Show through from the back | Ghost letters in the result | Increase contrast, or rescan with a dark backing |
| Wrong language | Nonsense words | Choose the right source language |
Privacy and confidentiality
Documents often hold sensitive information, such as names, addresses, ID numbers, medical details and financial figures. Crop or cover what you do not need to translate. Our tool reads the image in your browser, and only the extracted text is sent for translation, as explained in our privacy policy. For confidential documents, check your obligations first, and for highly sensitive ones consider a professional. Read more in whether image translation is safe and private.
Be realistic about accuracy
Clean scans of printed text in common languages translate well. Poor scans, complex layouts and specialist vocabulary reduce accuracy. Always check numbers, dates and names, and for anything important use the English as a guide and confirm with a professional. For advice on testing a result, see how accurate machine translation really is.
A worked example: a scanned rental contract
Imagine a landlord emails a scanned rental contract of twelve pages in German. You try to select text and find you cannot, so it is a scan. You open the file at a comfortable zoom and capture the first page as a screenshot, then paste it into the translator with German selected. While the translation appears, you note the rent, the deposit, the notice period and the clause about utilities, and you paste them into a working note under a heading for page one. You repeat the process for each page, marking any word you are unsure of. At the end, you have a one page summary of the key terms and a list of questions. You do not sign anything yet. Instead, you take the summary and the original to a lawyer, who can review the full contract in a fraction of the time, because you have already found the parts that matter.
Speeding up the process
- Use keyboard shortcuts for capturing and pasting, so each page takes seconds.
- Keep two windows side by side, with the PDF on one side and the translator on the other.
- Work in a quiet block of time, and take a short break every few pages to keep your attention sharp.
- Translate the first and last pages and any table of contents first, to decide whether the whole document is worth the effort.
Frequently asked questions
Can I translate a PDF with your tool?
You can translate a PDF page after turning it into an image, for example with a screenshot. If the PDF has selectable text, copying the text is simpler and more accurate.
How do I know whether my PDF is a scan?
Try selecting text or searching for a word. If you cannot, it is a scanned image.
Can I translate many pages at once?
The free tool handles one image at a time. Batch upload is planned for paid plans.
Will the layout be kept?
No. You get plain text, so tables and columns need to be rebuilt by hand.
Is a machine translation acceptable for official use?
Often not. Authorities may require a certified translation.
Next steps
Open a scanned page, capture it and run it through the translator. If you get errors, our guide on why OCR misreads text will help, and our document translator page has a quick checklist.