Image Format Converter

Image Format Converter and Resizer – Convert and Resize in One Tool

Convert images between JPG, PNG, WebP, AVIF, GIF, BMP, TIFF, ICO, PDF and SVG and resize by pixels right in your browser. The tool is a 2-in-1 converter + resizer: change format, quality and dimensions without uploading. Everything runs locally with Canvas, so your photos never leave your device. It handles iPhone HEIC/HEIF (decoded via heic2any), keeps transparency on a checkerboard, and shows a fullscreen overlay spinner with live % while converting. AVIF works in all modern browsers via native Canvas or automatic WASM fallback (@jsquash/avif) – the AVIF chip is always visible, never hidden.

How to Convert and Resize Images

1. Add images: Drop up to 20 files onto the dashed area or click Browse files / Upload in the top bar. Each file up to 10 MB. Accepted: JPG/JPEG, PNG, WebP, AVIF, GIF, BMP, ICO, TIFF, PDF, SVG, HEIC/HEIF.
2. Pick output format: Choose the chip in the top bar – JPG, PNG, WebP, AVIF, GIF, BMP, ICO, TIFF, PDF or SVG. AVIF is always visible; if your browser cannot encode AVIF natively it encodes via WASM automatically.
3. Quality (JPG/WebP/AVIF only): Drag Quality 10–100%. The label updates live as Quality 85%, conversion starts only after you press Convert. PNG/BMP/GIF/ICO/TIFF/PDF/SVG ignore quality (slider dims to 0.45 and disables). 85% is the sweet spot – 100% often makes files larger with no visible gain.
4. Background for transparency: If output is JPG, BMP, ICO or PDF and any source has transparency, set BG (color picker + hex like #ffffff). The preview square shows the color; it dims when the format does not need a background.
5. Resize (2-in-1): Toggle Resize in the top bar to show W × H + Lock aspect (🔒). Enter width or height (the other auto-calculates when locked) and press Apply to selected. Each row has a ☑ checkbox to choose which images to resize and a ↔ button to open per-image W/H that overrides the global size. Leave empty to keep original dimensions. Values are clamped to 1–8000px.
6. Convert: Press Convert. A fullscreen overlay spinner covers the page with live % progress – clicking outside does not close it. The list below switches from a dashed empty state to compact rows: 72px thumb (84px on desktop, 64px tablet) with format pill, two-line data – line 1 1200×800 · JPG → WebP pill (dimensions bold), line 2 1.2 MB → 340 KB bold (green if saved, red if larger) – plus Saved/Larger badge, Download and Remove. PDF shows a centered picture_as_pdf icon instead of a broken preview.
7. Download: One file with Download per row or all with Download ZIP (folder_zip) in the top bar. ZIP is built locally via JSZip. Names keep the original base: photo.jpg → photo.webp (or photo-1.webp for duplicates).

Inputs, Settings and Result

• Files: Drag & drop or browse. Supported inputs: JPG/JPEG, PNG, WebP, AVIF, GIF, BMP, ICO, TIFF, PDF, SVG, HEIC/HEIF. Up to 20 per batch, 10 MB each. Errors show inline.
• Output formats: JPG (image/jpeg), PNG (image/png), WebP (image/webp), AVIF (image/avif via Canvas or WASM), GIF (256 colors via gifenc), BMP (24-bit lossless), ICO (PNG wrapped, scaled to 256px), TIFF (via UTIF), PDF (one page per image via jsPDF), SVG (bitmap wrapped). HEIC is input-only.
• Quality: 10–100, live Quality 85%. Enabled for JPG/WebP/AVIF only.
• Background: Hex + picker, used only for JPG/BMP/ICO/PDF with transparency.
• Resize: Global W/H + Lock + Apply to selected, plus per-row checkbox and per-row W/H override. Checked rows follow global; unchecked keep original. Per-row custom overrides global.
• Result rows: List view (not grid) for fast scanning of 20 files. Thumb 72px (84px desktop) with checkerboard for transparent formats, format pill top-left, PDF icon for PDFs. Two-line meta as described, Saved/Larger badge (soft green #dcfce7 / soft red #fee2e2), Download pill and Remove. At 100% quality a yellow hint Larger than original at 100% – Re-convert at 85% appears.
• Stats header: Count, total original → total converted, Saved/Larger badge. Overlay spinner shows % during batch.

Why Convert and Resize Here

• 100% local, no upload: Canvas + WASM in your browser – private, fast, no server limits or CORS.
• Bulk 2-in-1: Convert format and resize dimensions in one click for 20 images – ideal for shops, blogs and social.
• True AVIF everywhere: Native where supported, automatic WASM fallback elsewhere – no disabled chip, no extra steps.
• Smart quality: 85% default saves ~40–70% vs 100% with no visible loss; warning + one-click 85% when larger.
• Modern UX: Full-width, no max-width, soft badges, 72→84px thumbs, two-line data, fullscreen spinner that cannot be dismissed by click.

FAQ – Quick Answers for Search and AI

Can I convert and resize at the same time?

Yes. Enable Resize, set W or H (Lock keeps aspect), Apply to selected, then Convert. The canvas is resized before encoding, so you get the new dimensions in the new format in one step.

Does AVIF work in Firefox and Safari?

Yes. If native canvas.toBlob('image/avif') is not supported, the tool lazy-loads @jsquash/avif WASM (~280KB gzipped) and encodes via speed 6, quality 50–85 in a Web Worker. The AVIF chip stays enabled with a tooltip.

Why is my PDF preview an icon?

PDF is application/pdf and cannot be shown in an <img>. Converted PDFs show a centered picture_as_pdf icon with a PDF label on a soft red tile.

How do I resize only some images?

Keep Resize enabled, uncheck the rows you want to keep original, or open ↔ on a single row and set its own W/H which overrides the global size.

What quality should I use for web photos?

Use 80–85% for JPG/WebP/AVIF. It looks identical to 100% but is 30–60% smaller. Use 100% only for archival.

Limits and Error Handling

• Max 20 files per batch; more shows You can convert up to 20 images at once.
• Max 10 MB per file; larger shows Each image must be 10 MB or smaller.
• Unsupported types show That file type is not supported. Use JPG, PNG, WebP, AVIF, GIF, BMP, ICO, TIFF, PDF, SVG or HEIC.
• HEIC via heic2any 0.0.4, GIF via gifenc 1.0.3, TIFF via UTIF 3.1.0, PDF via jspdf 2.5.1, ZIP via jszip 3.10.1, AVIF WASM via @jsquash/avif 2.1.1 – each lazy-loaded only when needed.
• Corrupt images show That image could not be read. All blob URLs are revoked on remove/clear to free memory.
• All processing is client-side. No upload, no cookies for images, no server storage.