A money flow diagram is a visual map of how money moves through your finances in a given period — usually a month. It shows income sources on the left, spending categories in the middle, and what is left (or overspent) on the right. The width of each flow line represents the amount, so you see at a glance where the biggest chunks of money go.
This type of chart is called a Sankey diagram. It is used in engineering to show energy flow, in logistics to show supply chains, and in personal finance to show cash flow. One look tells you more than a spreadsheet of numbers ever could.
What a money flow diagram shows you
The diagram starts with your income — salary, side gigs, investment returns — as a single wide band on the left. That band splits into narrower flows, each representing a spending category: housing, food, transportation, entertainment, debt payments, savings. The width of each flow is proportional to the dollars spent, so a four-hundred-dollar dining budget is visibly wider than a fifty-dollar streaming subscription.
At the right edge, you see what is left. If inflow exceeds outflow, the remaining band flows into savings or investments. If outflow exceeds inflow, the diagram shows a deficit — money you borrowed, pulled from savings, or put on a credit card.
The power of the diagram is that it makes proportion obvious. You might know you spend three hundred a month on groceries, but seeing that flow next to your two-thousand-dollar rent shows you the relative weight. You might think subscriptions are trivial, but when you see eight thin lines adding up to two hundred dollars, you realize they are not.
How to create your own money flow diagram
The manual way is to list your income sources and spending categories in a spreadsheet, then use a Sankey chart tool like SankeyMATIC or a Google Sheets plugin. You enter the flows as pairs — 'Income to Rent: 2000' — and the tool draws the diagram. It works, but it is tedious and you have to update it by hand every month.
The automatic way is to use a finance app that builds the diagram for you from your linked accounts. Mora generates a money-flow Sankey chart in real time, pulling from every transaction across all your connected banks and credit cards. The chart updates every six hours as new transactions sync, so you always see your current flow without entering a single number.
Other apps with flow visualization include Mint (basic flow charts, ad-supported) and Personal Capital (focused on net worth and investments). Most budgeting apps show spending by category as a pie chart or bar graph, which is useful but does not show the flow from income to spending to savings in one picture.
What to look for in your diagram
First, check the proportions. Is housing more than fifty percent of your income? That is a red flag unless you live in an expensive city and have no debt. Are dining and entertainment together larger than groceries? That is not wrong, but it is worth knowing.
Second, look for thin flows that add up. Subscriptions, fees, and small recurring charges often appear as many narrow lines that together form a significant chunk. If you see ten lines under 'Subscriptions and Services' totaling three hundred dollars, you have found a place to cut.
Third, check the right edge. If the diagram shows money left over, you are cash-flow positive — good. If it shows a deficit, you are spending more than you earn, which is sustainable only if you are drawing down savings intentionally or paying off debt that will end soon.
Using the diagram to fix your flow
Once you see the diagram, the fixes become obvious. A category that is too wide gets a spending limit and an alert when you are near it. Thin flows that do not serve you get canceled. Money that used to leak into miscellaneous spending gets redirected into a savings flow at the top of the diagram, before it can be spent.
Mora's diagram is interactive: tap a flow to see the transactions behind it, so you can drill from the big picture into the details in seconds. The AI companion can answer questions about the diagram in plain language — 'Why is my dining spending so high this month?' — and it will list the largest transactions and compare them to previous months.
The diagram is not a budget. It is a mirror. It shows you what actually happened, and once you see it, you can decide what to change.
