100KB Extension v1.1.1: Compress & resize files in 0ms directly in Google Chrome
Convert PNG and WebP images to JPG format online instantly. Compress file size to target KB limits for form uploads. Formatted for HMPO UK Passport.
To ensure your photo is accepted by the United Kingdom official platform, it must meet the following strict criteria:
Disclaimer: These requirements are verified based on official guidelines. However, platform rules and guidelines can change. Always consult the official HMPO UK Passport portal before final submission.
Her Majesty's Passport Office (HMPO) is notoriously strict regarding digital shadows, glare, and background hues, frequently rejecting unverified selfies. By using this automated formatting tool, your picture is instantly resized to the mandatory 45mm tall by 35mm wide dimensions while preserving the required high-definition clarity. PNG graphics preserve lossless 32-bit RGBA pixels and transparent background layers, resulting in heavy file sizes (often 3MB to 8MB) that exceed portal upload limits.
Converting PNG to JPG replaces transparent alpha pixels with a solid white background (#FFFFFF) and applies Discrete Cosine Transform (DCT) quantization to shrink file payload by up to 85% while preserving visual clarity.
| Format | Quantization Engine | Color Space & Subsampling | Target Size Ceiling | Portal Acceptance |
|---|---|---|---|---|
| JPEG / JPG | Lossy 8x8 DCT Frequency Quantization | YCbCr (4:2:0 Subsampling) | 20KB – 500KB | 100% (Universal Exam & Visa Portals) |
| PNG | Lossless Deflate / LZ77 Filtering | RGB + 8-bit Alpha Channel | 100KB – 2MB | E-commerce, Logos & Digital Design |
| WEBP | VP8 Intra-frame Prediction | YCbCr 4:2:0 / Lossless | 15KB – 300KB | Modern Web Apps & Mobile Display |
Follow these simple steps to ensure your file meets all requirements for HMPO UK Passport.
Select PNG images from your computer or phone. Stand roughly 1.5 meters away from the camera in front of a plain, light-coloured wall with no objects visible.
Choose JPEG compression level and optional target size cap. Align the on-screen guides so that the distance from your chin to the top of your head measures exactly 29 to 34 millimeters.
Click Convert to flatten alpha layers and encode JPEG. Save the final JPEG document, optimized to satisfy the strict 50KB - 10MB digital parameters for the UK GOV portal.
Answers to common questions regarding requirements for HMPO UK Passport.
Lead WebAssembly Systems Engineer at 100KB Tools. Technical specifications researched and cross-verified against official ICAO Doc 9303 Part 9 standards, ISO/IEC 10918-1 JPEG specifications, and PDF/A ISO 19005 guidelines.
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