Interior Design
Fee Calculator

What the Fee Calculator Does

The Interior Design Fee Calculator walks you through every phase of a standard interior design project to produce an itemised fee estimate based on the services you select and the fee model you choose.

Although it is not a generic pricing tool, it reflects the actual structure of interior design work, from your initial client consultation to client sign-off and project handover. This means that the output you get from it is relevant to how interior design projects are actually run. It is strictly a niche-specific tool created for residential and commercial designers, and professional interior decorators.

Choosing Your Fee Model

The first decision the fee calculator asks you to make is to choose a fee model. There are three options:

1. Flat fee
2. Hourly rate
3. Percentage over costs

Flat Fee Model

With this model, you assign a fixed amount to each service line item. This structure works well for experienced designers who have a clear sense of how long each phase may take and wish to offer their clients a pricing certainty upfront.

Hourly Rate Model

This model asks you to enter your rate once, then it estimates the number of hours per service. The fee calculator does the multiplication. This is a common model for designers who are still building their project history and prefer to bill for their time, rather than commit themselves to a fixed scope.

Percentage of Project (% over costs)

This budget model is typically used for larger residential or commercial projects where the design fee is charged, based on the total expenditure. You enter the total project budget and assign a percentage to each service phase. This model rewards project complexity. The larger and more involved the project is, the higher the returns for your time and service.

Adding Rooms and Spaces

Before working through the service phases, the calculator allows you to log the rooms (or spaces) included in the project. You can add as many rooms as the project requires: a single living room for a focused brief, or a full list covering every space in a larger home or commercial business. Each room entry includes a field for square meters/feet. This figure does not affect the fee calculation. It serves as a useful reference point when reviewing or presenting your estimate and it becomes part of the printed output.

Working Through Phases

The calculator is structured across four phases, preceded by a consultation section. Each service within a phase can be toggled on or off, depending on the specific project scope. For instance, if a service does not apply, just untick it. It will disappear from the final estimate.

Consultation Services

This covers your initial meeting with the client and any associated travel (car, train, plane).

Phase One: Design Development

After consultation with clients, the first phase commences. It covers:

• Concept development
• Design presentation/mood boards
• 3D visualisation/rendering
• Documentation
• Site visits
• Revision rounds

Phase Two: Procurement and Implementation

Phase Two involves procurement and project implementation, including:

• Materials sourcing
• Product procurement
• Supplier liaison
• Delivery coordination
• Storage coordination
• Fitters & installers coordination

Phase Three: Project Management and Supervision

This phase addresses project management and supervision, including:

• Project implementation management
• Site supervision
• Snagging/punch list review
• Final site inspection

Phase Four: Completion & Handover

This stage covers the project completion and handover to the client. It covers:

• Client walkthrough and sign-off
• As-built documentation
• Care and maintenance guide handover
• Post-project review/feedback session

This structure of Phases 1-4 mirrors the professional practice framework used by industry bodies, including the BIID. It also reflects how clients expect a project to be managed.

Reading Your Results

After you fill your required fields and click Calculate Fee Estimate, the interior design fee calculator tool produces a clean, itemised breakdown organised by phase, with a subtotal for each section, and a Grand Total at the bottom. The output includes your client’s name, project reference, location, and chosen fee model, all drawn from your entries.

The results page includes a print and export function that allows you to save the estimate as a PDF directly from your browser. You can then attach it to a proposal or keep it in a physical file.

A Fee Calculator Tool Worth Returning To

No two projects are the same. A studio apartment refresh and a full commercial fit-out require completely different scopes, and your fee should reflect that difference every time. Bookmark this page and use the calculator each time a new brief land on your desk. The few minutes it takes to work through the phases will sharpen your thinking, anchor your fee to real scope, and give you the confidence to quote without second-guessing yourself.