Tutorial 099Design Tools14 steps4 fixes

How to Choose a Web Image Format

A beginner, interface-by-interface guide to choose a web image format, including what each design term means, where to click and how to verify the exported/resulting asset.

By the end: You will complete choose a web image format and keep an editable source plus a checked output.

TARGET RESULTHow to Choose a Web Image Format
You will complete choose a web image format and keep an editable source plus a checked output.

Key terms before you start

These definitions make the steps easier to follow and help distinguish controls, files and concepts that can look similar at first.

Raster imageAn image made from a grid of pixels, such as a photograph.

Pixel dimensionsRaster width and height in pixels; for the web these directly affect detail and often file size.

ExportCreating a delivery file such as PNG/JPEG/WebP from an editable working file.

LayerAn independently editable object in an image/design document; Photoshop and GIMP stack layers.

What you need before starting

Access to browser/image editor
A source/project you are allowed to edit
A clear final destination/size/use for the result

FULL TUTORIAL

Step-by-step tutorial

Every step is shown below. Work through them in order and use each checkpoint to confirm the result before moving on.

STEP 01 / 14

Open browser/image editor and use a safe working copy

Do this

Open the real project in browser/image editor. Duplicate the file/document first if the tutorial could alter important source work.

Why

The editable source is different from the final exported asset; preserve recoverability.

ExportCreating a delivery file such as PNG/JPEG/WebP from an editable working file.

IF THIS GOES WRONGThe exported result differs from the canvas

Inspect export dimensions, transparency, crop, color and output format; judge the exported file as the final artifact.

CHECKPOINTA working copy or recoverable source is open.

STEP 02 / 14

Identify the final destination

Do this

Write where the result will be used: website width, social platform, handoff, print, prototype, etc.

Why

Dimensions, color, format and responsive behavior depend on destination.

Pixel dimensionsRaster width and height in pixels; for the web these directly affect detail and often file size.

IF THIS GOES WRONGThe exported result differs from the canvas

Inspect export dimensions, transparency, crop, color and output format; judge the exported file as the final artifact.

CHECKPOINTThe target is explicit.

STEP 03 / 14

Identify whether asset is raster or vector

Do this

Photographs are raster; logos/icons may be true vector artwork.

Why

Do not convert a photo to SVG expecting vector scalability.

Raster imageAn image made from a grid of pixels, such as a photograph.

CHECKPOINTAsset type known.

STEP 04 / 14

Check whether transparency is required

Do this

Transparent UI/logo assets need alpha support.

Why

Format choice depends on features.

IF THIS GOES WRONGThe exported result differs from the canvas

Inspect export dimensions, transparency, crop, color and output format; judge the exported file as the final artifact.

CHECKPOINTTransparency requirement known.

STEP 05 / 14

For photographs, export two modern/legacy candidates

Do this

Compare JPEG/WebP/AVIF depending on site/browser/tool support.

Why

Choose based on measured quality/bytes, not fashion.

ExportCreating a delivery file such as PNG/JPEG/WebP from an editable working file.

IF THIS GOES WRONGThe exported result differs from the canvas

Inspect export dimensions, transparency, crop, color and output format; judge the exported file as the final artifact.

CHECKPOINTCandidate files exist.

STEP 06 / 14

For raster transparency, test PNG versus suitable modern format

Do this

PNG is lossless and can be large for photos.

Why

Use it when lossless raster/transparency is justified.

Raster imageAn image made from a grid of pixels, such as a photograph.

IF THIS GOES WRONGThe exported result differs from the canvas

Inspect export dimensions, transparency, crop, color and output format; judge the exported file as the final artifact.

CHECKPOINTTransparent edges correct.

STEP 07 / 14

For true vector logos/icons, keep SVG when safe/appropriate

Do this

SVG scales without raster pixelation.

Why

Sanitize/trust SVG sources and ensure CMS/security policy allows them.

Raster imageAn image made from a grid of pixels, such as a photograph.

IF THIS GOES WRONGYou lost editability

Return to the layered/component source or backup. Keep future export/flatten operations on separate delivery copies.

CHECKPOINTVector remains sharp at multiple sizes.

STEP 08 / 14

Match pixel dimensions for raster comparisons

Do this

Compare formats at same dimensions.

Why

A smaller file caused by smaller pixels is not a fair codec comparison.

Pixel dimensionsRaster width and height in pixels; for the web these directly affect detail and often file size.

IF THIS GOES WRONGThe exported result differs from the canvas

Inspect export dimensions, transparency, crop, color and output format; judge the exported file as the final artifact.

CHECKPOINTDimensions equal.

STEP 09 / 14

Inspect at final display size

Do this

Look for ringing, block artifacts, text edge damage or transparency halos.

Why

Numerical file size alone is not quality.

Pixel dimensionsRaster width and height in pixels; for the web these directly affect detail and often file size.

IF THIS GOES WRONGThe exported result differs from the canvas

Inspect export dimensions, transparency, crop, color and output format; judge the exported file as the final artifact.

CHECKPOINTVisual result acceptable.

STEP 10 / 14

Measure bytes

Do this

Use file properties or browser Network.

Why

Record actual transfer size.

Pixel dimensionsRaster width and height in pixels; for the web these directly affect detail and often file size.

IF THIS GOES WRONGThe exported result differs from the canvas

Inspect export dimensions, transparency, crop, color and output format; judge the exported file as the final artifact.

CHECKPOINTSmaller acceptable candidate identified.

STEP 11 / 14

Upload and inspect Content-Type/rendering

Do this

Confirm server/browser serves and displays correctly.

Why

Misconfigured MIME type/caching can break otherwise valid assets.

IF THIS GOES WRONGThe exported result differs from the canvas

Inspect export dimensions, transparency, crop, color and output format; judge the exported file as the final artifact.

CHECKPOINTPublic asset loads.

STEP 12 / 14

Keep editable source separately

Do this

Do not rely on compressed delivery file as future master.

Why

Repeated lossy re-exports degrade quality.

ExportCreating a delivery file such as PNG/JPEG/WebP from an editable working file.

IF THIS GOES WRONGYou lost editability

Return to the layered/component source or backup. Keep future export/flatten operations on separate delivery copies.

CHECKPOINTMaster remains available.

STEP 13 / 14

Open the exported/result outside the editor

Do this

Inspect the actual PNG/JPEG/SVG/prototype/output rather than assuming it matches the canvas.

Why

Exports can change dimensions, transparency, font rendering or compression.

ExportCreating a delivery file such as PNG/JPEG/WebP from an editable working file.

IF THIS GOES WRONGThe exported result differs from the canvas

Inspect export dimensions, transparency, crop, color and output format; judge the exported file as the final artifact.

CHECKPOINTOutput is correct.

STEP 14 / 14

Store source and delivery files predictably

Do this

Use clear names/versioning and keep the source separate from public delivery assets.

Why

Future revisions should start from editable source.

ExportCreating a delivery file such as PNG/JPEG/WebP from an editable working file.

IF THIS GOES WRONGYou lost editability

Return to the layered/component source or backup. Keep future export/flatten operations on separate delivery copies.

CHECKPOINTFiles can be found/reused.

Concrete examples

Beginner ruleAlways know whether you are editing source structure or generating a delivery copy.

Troubleshooting

You edited the wrong layer/frame

Undo, then select the target through Layers panel and verify its name before editing.

The exported result differs from the canvas

Inspect export dimensions, transparency, crop, color and output format; judge the exported file as the final artifact.

A long label/content breaks the design

Use Auto Layout/flexible components or revise layout constraints rather than shrinking type until it barely fits.

You lost editability

Return to the layered/component source or backup. Keep future export/flatten operations on separate delivery copies.

FINAL CHECKStore source and delivery files predictably
Files can be found/reused.

Documentation and references

Use these primary and supporting sources to verify current controls, browser behavior and product-specific details.

← How to Use Layer Masks in GIMP How to Create Consistent Social Media Graphics in Canva →

Key terms before you start

What you need before starting

Step-by-step tutorial

Open browser/image editor and use a safe working copy

Identify the final destination

Identify whether asset is raster or vector

Check whether transparency is required

For photographs, export two modern/legacy candidates

For raster transparency, test PNG versus suitable modern format

For true vector logos/icons, keep SVG when safe/appropriate

Match pixel dimensions for raster comparisons

Inspect at final display size

Measure bytes

Upload and inspect Content-Type/rendering

Keep editable source separately

Open the exported/result outside the editor

Store source and delivery files predictably

Concrete examples

Troubleshooting

Continue with these tutorials

Documentation and references