This article is updated every year to give people who are planning on coming to Japan an accurate idea of just how much daily items will cost them so that they can plan their budget accordingly.
To calculate just the total amount of savings you will want to prepare when coming to Japan, you will also need to take into account the Average costs of rent per city and Estimated costs for Tuition for those going to school.

For everything else, we have created this article to illustrate the daily expenses of things like groceries, mobile phone bills and utilities.

Groceries: Food costs

Grains & Rice
Bag of rice 5kg: ¥2500
Mini loaf of bread (6 slices): ¥200~300

Meat, Poultry, Fish
Beef: ¥200/100g
Pork: ¥150/100g
Pork Ribs: ¥100/100g
Chicken: ¥100/100g
Fish: ¥100/100g (average: ¥200/100g)

Fruits & Vegetables
Cabbage: ¥100~¥200 (depending on type)
Cucumber: ¥100 ~ ¥200 / for 3 whole
Most other vegetables: ¥100~¥200 / bunch
Tomato: ¥100 / 1 each
Banana: ¥100 / each
Apple: ¥100 / each
Peach: ¥200 / each (average: ¥400)
Most other fruit: ¥100 / each

Miscellaneous
Sugar: ¥200/kg
Salt: ¥200/kg
Fish sauce: ¥400/bottle of 300ml
Instant noodles: ¥100/pack
Supermarket ready-made meals (donburi, curry on rice, omurice): ¥300~¥600

Groceries: Drink costs

Mineral water: ¥100~¥200 / 1.5L
Green tea, flavoured or milk tea: ¥200 / 1.5L
Milk: ¥200 / 1L
Juice (apple, orange): ¥100~¥200 / 1L

Can of local beer (330mL): ¥200
Can of craft beer (330mL): ¥300 ~ ¥400
Can of pre-mixed drink (330mL): ¥200
Bottle of cheaper wine (750mL): ¥800~¥1200
Bottle of imported wine (750mL): ¥1600 ~ ¥4000

Mobile & Utilities

Mobile telephone plan: from ¥2000~¥5000 per month
Transportation costs by train: approximately ¥200 every 20 minutes, per line (average)
Combined utilities (electricity, water, gas, internet, garbage): ¥10,000 (maximum)

Dining out

Donburi (meat & vegetables on rice): ¥400~¥600)
Bowl of Ramen: ¥600~¥900
Bowl of soba or udon noodles: ¥400 ~ ¥700
Teishoku (Rice, salad, main, sides): ¥600~¥1,200
Bento: ¥500~¥700
Most meals for dinner at restaurants: ¥1200~¥1800

Glass of local beer (on tap): ¥600~¥700
Glass of craft beer (on tap): ¥700~¥900
Glass of wine: ¥600~¥900