# AI Anime Upscaler > Kenerate's AI anime upscaler enlarges anime art, manga pages, stickers and AI anime renders without blurring the line art. The default Real-ESRGAN engine keeps clean outlines and flat colours; Image Upscaler outputs exact 4K or 8K. In our tests a 256 px chibi sticker came out at 2048 px and a 320 px manga panel at 1832 × 2290. 25 free credits, no watermark. URL: https://kenerateai.com/anime-upscaler Publisher: Kenerate AI (https://kenerateai.com) Last updated: 26 September 2026 ## Key facts - Engine: Real-ESRGAN (default) - Watermark: None - Max size: 8K or 128 MP - Best format: PNG for line art ## Steps 1. Add the anime image — Upload fan art, a screenshot, a manga page, a sticker or an AI anime render — JPG, PNG or WEBP up to 25 MB. 2. Keep Real-ESRGAN selected — It is the default engine and keeps clean line art and flat colours. For a fixed 4K or 8K size, pick Image Upscaler. 3. Download a PNG — Compare the lines at 100% and download — PNG keeps flat colours and outlines crisp. No watermark. ## In depth ### Line art breaks normal resizing Anime and manga are built from hard ink edges and flat fills. Ordinary interpolation — bilinear or bicubic — averages neighbouring pixels, which turns crisp black lines into soft grey ramps and makes flat areas blotchy [1][2]. Nearest-neighbour keeps edges hard but turns every curve into a staircase [1]. ### waifu2x: the first popular anime upscaler waifu2x, released by nagadomi in 2015 under the MIT licence, applied the SRCNN idea [3] to anime-style art and added noise reduction for JPEG artefacts [4]. It is still maintained — development moved to the PyTorch project nunif in 2023 [5]. ### Real-ESRGAN's anime model Real-ESRGAN (2021) is trained on synthetic real-world damage — blur, noise, resizing and JPEG — so it handles screenshots and reposts that have been compressed several times [6]. Its authors also publish RealESRGAN_x4plus_anime_6B, a smaller model optimised for anime images [7]. Kenerate's default engine is Real-ESRGAN, which is why line art stays dark and clean. ### Keep characters on-model Generative upscalers can add texture that was never drawn — great for paintings, wrong for cel-shaded characters. The perception–distortion trade-off means more invented detail always costs some faithfulness [8]. For character art, stay with Real-ESRGAN or Image Upscaler and download PNG. References: [1] Image scaling — Wikipedia: https://en.wikipedia.org/wiki/Image_scaling [2] Keys (1981) — Cubic convolution interpolation: https://doi.org/10.1109/TASSP.1981.1163711 [3] Dong et al. — SRCNN (ECCV 2014 / TPAMI 2016): https://arxiv.org/abs/1501.00092 [4] waifu2x — GitHub (nagadomi, MIT): https://github.com/nagadomi/waifu2x [5] nunif — GitHub (waifu2x successor): https://github.com/nagadomi/nunif [6] Wang et al. — Real-ESRGAN (ICCV Workshops 2021): https://arxiv.org/abs/2107.10833 [7] Real-ESRGAN — GitHub (BSD-3-Clause, anime model): https://github.com/xinntao/Real-ESRGAN [8] Blau & Michaeli — The Perception-Distortion Tradeoff (CVPR 2018): https://arxiv.org/abs/1711.06077 ## FAQ Q: What is the best anime upscaler? A: For clean line art and flat colours, a Real-ESRGAN-based upscaler is the usual choice — it is what Kenerate uses by default. waifu2x is the classic free option at up to 2× on its web demo; Kenerate goes to 4K, 8K or 128 MP. Q: How do I upscale an anime image without blur? A: Use an AI upscaler rather than a normal resize. Upload the image to Kenerate, keep Real-ESRGAN selected and download a PNG: lines stay sharp instead of turning soft and grey. Q: Can I upscale manga pages? A: Yes. Real-ESRGAN keeps black ink lines and screentone clean. Scan or save the page as PNG where possible, since JPEG blocks show up in flat areas. Q: Will the upscaler change the character's face? A: Real-ESRGAN and Image Upscaler are faithful — they enlarge and sharpen without redrawing. Creative engines like Clarity Pro can add detail and change small features, so avoid them for character art that must stay on-model. Q: What format should I download? A: PNG for anime and line art: it has no compression blocks in flat colours. Use WEBP or JPG only when file size matters. Q: Is it free? A: Free to start: 25 free credits on sign-up to test it on your own images; bigger jobs use one-time credit packs that never expire. No watermark. ## Related pages - AI image upscaler: https://kenerateai.com/ai-image-upscaler - Upscale image: https://kenerateai.com/upscale-image - AI image enhancer: https://kenerateai.com/ai-image-enhancer - Upscale image to 4K: https://kenerateai.com/upscale-image-to-4k - Increase image resolution: https://kenerateai.com/increase-image-resolution - HD photo converter: https://kenerateai.com/hd-photo-converter - Unblur image: https://kenerateai.com/unblur-image - Sharpen image: https://kenerateai.com/sharpen-image - Unpixelate image: https://kenerateai.com/unpixelate-image - Photo restoration: https://kenerateai.com/photo-restoration - Uncensored image enhancer: https://kenerateai.com/enhance-ai - Enhance AI art: https://kenerateai.com/enhance-ai-art - Bulk image upscaler: https://kenerateai.com/bulk-image-upscaler - Remove glare from photo: https://kenerateai.com/remove-glare-from-photo - Restore old photos: https://kenerateai.com/how-to-restore-old-photos - Best photo restoration software: https://kenerateai.com/best-photo-restoration-software - Denoise photos: https://kenerateai.com/how-to-denoise-photos - Increase image resolution: https://kenerateai.com/how-to-increase-resolution-of-an-image - Sharpen an image in Photoshop: https://kenerateai.com/how-to-sharpen-an-image-in-photoshop - All upscaler alternatives: https://kenerateai.com/image-upscaler-alternatives - Remini alternative: https://kenerateai.com/remini-alternative - Let's Enhance alternative: https://kenerateai.com/lets-enhance-alternative - upscale.media alternative: https://kenerateai.com/upscale-media-alternative - Upscayl online: https://kenerateai.com/upscayl-online - Bigjpg alternative: https://kenerateai.com/bigjpg-alternative - VanceAI alternative: https://kenerateai.com/vanceai-alternative - waifu2x alternative: https://kenerateai.com/waifu2x-alternative - Magnific AI alternative: https://kenerateai.com/magnific-ai-alternative - Topaz Labs alternative: https://kenerateai.com/alternatives/topazlabs-alternative ## Sources - Real-ESRGAN — GitHub (includes an anime model): https://github.com/xinntao/Real-ESRGAN - waifu2x — GitHub: https://github.com/nagadomi/waifu2x