The best screenshot format depends on where the picture is going. A bug report with small text, a photo-heavy presentation slide, and a document attachment have different needs. The lightingshot editor exports PNG, JPEG, and an image-based A4 PDF. All three are generated locally from the current canvas, including your crop and annotations.
A quick decision table
| Your main need | Start with | Check before sending |
|---|---|---|
| Readable interface text, diagrams, and annotation edges | PNG | The recipient can read the image at its intended size. |
| A photograph or photo-heavy screenshot | JPEG | Compression has not made small text or edges distracting. |
| A document attachment with A4 pages | Image PDF | Every page is legible and page breaks do not cut important details. |
These are starting points rather than file-size promises. Export the format that fits your delivery destination, then inspect the actual result.
PNG for sharp screenshot details
PNG uses lossless compression. JPEG normally discards some image information as part of compression, which can introduce visible artifacts around text and hard edges. That makes PNG a useful first choice for software interfaces, diagrams, and annotations, while JPEG often suits photographs. These general format differences are described in MDN's image format guide.
For example, if you have captured a spreadsheet error and added a red arrow, start with PNG. Open the download and inspect the smallest relevant number and the arrowhead. A clean PNG cannot restore detail that was already missing from the original screenshot, but it avoids adding another lossy JPEG encoding step to that export.
JPEG when photographic content dominates
A screenshot containing a large photograph may be a reasonable candidate for JPEG, especially when a recipient or upload form has a size limit. lightingshot exports JPEG at a fixed encoder quality setting in this release. There is no adjustable compression slider or guaranteed target file size.
Try a JPEG copy and compare the actual file size with the PNG copy using your device's file information. Then inspect any small captions, UI labels, and colored lines. If the JPEG version is still too large, crop irrelevant areas rather than repeatedly exporting copies of copies. Importing an already compressed image and re-encoding it does not recreate the original detail.
What the PDF export actually contains
lightingshot's PDF is a document of image slices. The writer scales the canvas width to the available width of an A4 page with margins, divides a tall image into successive vertical sections, and embeds those sections as JPEG pictures. A long screenshot can therefore become several PDF pages.
This output does not preserve the source webpage's text, headings, hyperlinks, form fields, or document structure. You cannot rely on selecting or searching the original words, and a link that looks blue in the picture is not a clickable webpage link. There is no OCR step. Choosing PDF is a packaging choice for the picture, not a conversion into an editable text document.
Page slicing follows image geometry rather than paragraphs. A line of text, chart, or table row can cross a page boundary. Preview every page and adjust the source crop if a break obscures the point. A very wide screenshot can also become difficult to read when fitted to A4 width. A tighter crop or several separately prepared images may communicate the content better.
Export and inspect the right copy
- Finish the edit. Import your image, crop unwanted borders, and add any annotations. Cover private details before generating files you might share.
- Open export. Select 导出图片 (Export image) at the upper right.
- Choose a format. Under 格式 (Format), choose PNG, JPEG, or PDF · A4 分页图片文档 (PDF, A4 paginated image document).
- Save a distinct file. Enter a descriptive filename and select 下载文件 ↓ (Download file). The download uses the selected format's extension.
- Open the saved result. Check readability, all PDF pages where relevant, and any attachment size restriction. Make sure the file you send is the version you inspected.
When the format is not the problem
If an export fails, a different extension alone may not solve it. The editor uses browser memory to render the image, and exceptionally large pictures may exceed available resources. Imports are limited to 40 MB, 32,000 pixels per side, and 80 million pixels overall; those upper limits do not promise every device will handle the largest allowed image comfortably.
The zoom buttons change your editing view without reducing export dimensions. Cropping reduces the retained area; choosing Fit to window does not. If a download never starts, check the browser's download permissions and follow the help checklist. Keep the original if you will need a different crop or format later.