Difference Detailed, How different are Redmi 9 and Redmi 8 from each other?

Redmi 9 vs Redmi 8: Price compared
redmi 9 has been introduced in Spain and its 3GB + 32GB storage option is priced at 149 euros (approximately Rs 12,800). Its 4GB + 64GB storage option is priced at 179 euros (approximately Rs 15,300). Pre-orders for the Redmi phone will start from June 15, and during pre-orders, the 3GB RAM and 4GB RAM variants of the Redmi 9 will be available for purchase at an introductory price of 139 euros (approximately Rs 11,900) and 169 euros (approximately Rs 14,500), respectively. The phone will go on sale in Spain on June 18 through online and offline retailers.
On the other hand, Redmi 8 The 4GB + 64GB storage variant of the phone is available for purchase in India for Rs 9,499. The phone is offered in Emerald Green, Onyx Black, Ruby Red and Sapphire Blue color options.
Redmi 9 vs Redmi 8: Specifications compared
The dual-SIM (Nano) Redmi 9 features a 6.53-inch full-HD+ (1,080×2,340 pixels) display with a waterdrop style notch, 19.5:9 aspect ratio, 394 ppi pixel density, and 400 nits brightness. It has Corning Gorilla Glass 3 protection. The phone works on a 2GHz MediaTek Helio G80 octa-core processor and comes with Mali-G52 GPU and up to 4GB of RAM. Internal storage supports up to 64GB, which can also be expanded using a dedicated microSD card slot.
On the other hand, the dual-SIM Redmi 8 runs MIUI 10 based on Android 9 Pie. It has a 6.22-inch HD+ (720×1,520 pixels) dot notch display with Corning Gorilla Glass 5 protection. It has an octa-core Qualcomm Snapdragon 439 processor with up to 4GB of RAM. Xiaomi has provided up to 64GB of storage in its Redmi 8. The handset has support for microSD cards up to 512GB.
The Redmi 9 has a quad camera setup at the back, which includes a 13-megapixel primary sensor with f/2.2 aperture, an 8-megapixel ultra-wide lens with f/2.2 aperture and 118-degree field-of-view, a 5-megapixel macro shooter with f/2.4 aperture, and a 2-megapixel depth sensor. The rear camera has features like kaleidoscope, ultra-wide-angle mode, macro mode, portrait mode, and 1080p recording support at 30fps. The Redmi 9 has an 8-megapixel selfie camera with f/2.0 aperture and 77.8-degree field-of-view. Front camera features include palm shutter, portrait mode, HDR, screen flash, self-timer, and more.
Talking about Redmi 8, it has a dual rear camera setup. The primary camera is 12 megapixels. It is a Sony IMX363 sensor and has an F/1.8 lens. It is accompanied by a 2 megapixel sensor. It is worth noting that the primary sensor used in this phone has also been used in Mi Mix 2S and Poco F1. Apart from this, the camera setup is equipped with AI portrait and AI scene detection. There is an 8 megapixel camera on the front. It has features equipped with artificial intelligence.
The Redmi 9 comes with a large 5,020mAh battery with 18W Quick Charge 3.0 fast charging support. The company provides a 10W charger inside the box. The Redmi 9 also supports AI Face Unlock and comes with a rear fingerprint sensor. The Redmi 8 has a 5,000mAh battery. It supports 18W fast charging. However, a 10W charger is provided in the retail box.
The Redmi 9 measures 163.32×77.01×9.01mm and weighs 198 grams. The Redmi 8 is smaller and lighter than its successor. It measures 156.3×75.4×9.4mm and weighs 188 grams.