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Image stretcher

Stretch image with DPI

Control DPI while stretching images in your browser. Physical sizes (inches, cm, mm) convert to pixels via DPI — preview on canvas and download PNG or JPEG. We never upload your file.

Preview
Controls

Stretch Template

Aspect

Unit

Stretch factors (non-uniform)

Horizontal1.00×
Vertical1.00×

Working with DPI

DPI maps physical units to pixels (1 in × 300 DPI = 300 px). Switch unit pills above, then pick a DPI preset or enter a custom value.

What DPI control solves when stretching

Print shops and forms often expect a physical size at a stated DPI. Stretching only in pixels ignores that contract. ImageStretcher lets you enter inches, cm, or mm and convert through DPI so the exported bitmap matches the print-ready pixel count.

Common presets — 72, 96, 150, 300 — cover screen and print. Default 300 DPI suits most home and shop prints. Adjust DPI live; the canvas still paints pixels under the hood.

No upload, no account. Set DPI, stretch axes independently, and download PNG or JPEG without handing the original to a cloud resizer.

How to stretch an image with DPI

Four steps from file to a DPI-aware download. The whole flow runs in the browser.

  1. Step 1

    Open an image

    Drop a PNG or JPEG into the upload area. Nothing is sent to a server — the browser reads the file into memory.

  2. Step 2

    Choose a physical unit and DPI

    Switch to inches, cm, or mm, then pick a DPI preset (72 / 96 / 150 / 300) or type a custom DPI. Width and height convert to pixels using that DPI.

  3. Step 3

    Preview the stretch

    The canvas updates as you adjust size and DPI so you can judge the remapped bitmap before export.

  4. Step 4

    Download

    Export PNG or JPEG. The file is a pixel bitmap sized from your physical inputs × DPI — the original stays on disk.

When DPI matters for stretching

Jobs where physical size plus DPI beats guessing pixel dimensions.

  • Print-ready proofs

    Match a print shop’s inch or cm size at 300 DPI without rebuilding the layout in a design app.

  • ID and passport boxes

    Forms often list mm sizes. Enter mm, set DPI, stretch to fill the box, then export locally.

  • Screen vs print

    72 or 96 DPI for screen mockups; 150–300 for print. Same stretcher, different DPI presets.

  • Catalog and flyer fills

    When cropping would cut text, unlock aspect, set physical size + DPI, and stretch to the paper box.

  • Private client files

    DPI conversion stays in the browser — no cloud upload of proofs or identity photos.

Why stretch in DPI with ImageStretcher

  • Independent axes

    Stretch width and height separately in DPI — or lock aspect when you need a clean proportional resize. Pixel fields and scale sliders share the same canvas truth.

  • Private by design

    No upload, no account. Canvas processing keeps DPI edits on your machine from open through download.

  • Instant preview

    See the DPI stretch live before you download PNG or JPEG. Adjust, compare, then export once the framing feels right.

  • Free and local

    Works offline once the page is loaded — no cloud round-trip for every tweak. Stretch in DPI and save without a subscription wall.

Formats and limits for DPI stretching

Open common bitmap files from your device — typically PNG and JPEG. Export the stretched result as PNG when you want crisp edges, or JPEG when file size matters. JPEG export includes a quality slider so you can trade a little clarity for a lighter download.

Processing is capped by what your browser and device can hold in memory. Very large megapixel photos may feel slower on older phones; if preview lags, try a smaller source or a modest output size in DPI. There is no server-side quota because there is no upload.

We do not store your pictures. Once you leave the page, in-memory previews are gone unless you downloaded a file. Stretch in DPI without handing the original to a third-party uploader.

Before and after — DPI stretch

Illustration only — not user uploads. The left card is the starting frame. Horizontal stretch widens the shape; vertical stretch elongates it. Real photos behave the same way in the DPI tool above: each axis is an independent remapping of the bitmap.

Use these sketches to build intuition, then open your own file and work in DPI. Compare subtle fills against exaggerated proportions so you know how far to push scale before export.

Before
After — horizontal
After — vertical

Stretch image with DPI FAQ

What does DPI do in ImageStretcher?
DPI converts physical units (inches, cm, mm) to pixels. Pixels ignore DPI. Export is always a pixel bitmap sized from physical × DPI.
What DPI should I use for printing?
300 DPI is a common default for home and shop prints. Use 150 for drafts, or follow your printer’s stated DPI.
Do you upload my images when I set DPI?
No. DPI conversion and stretching run entirely in your browser. Nothing is uploaded to our servers.
Can I stretch width without changing height with DPI?
Yes. Unlock aspect ratio and adjust width or height in a physical unit. DPI still maps those values to pixels.
Is the DPI tool free?
Yes. No account and no payment. Open a file locally, set unit and DPI, stretch, and download PNG or JPEG.