High Efficiency Image Container (HEIC) applies H.265 (HEVC) intra-frame compression achieving roughly twice the efficiency of JPEG at equal visual quality, used natively by Apple devices. AV1 Image File Format (AVIF) applies AV1 intra-frame compression delivering 50% smaller files than JPEG at equivalent quality, with wide colour gamut support. This conversion changes the file's encoding, compression method, and supported feature set. Colour profiles and orientation metadata are preserved in the output. The result is a standard AVIF file readable by any compatible application. 1converter handles HEIC-to-AVIF conversion server-side: files are uploaded over HTTPS, processed on isolated cloud infrastructure, and the converted output is available for download for 24 hours before automatic deletion. No account is required for standard conversions.