Build vs buy calculator

Should you buy software, build it, or do both?

Custom software is powerful, but it is not always the right call. Answer a few honest questions about your situation and get a clear recommendation, including when off-the-shelf is the sensible choice.

01How specialised is your core workflow?

Do you work broadly like others in your sector, or in an unusual way?

02Does suitable off-the-shelf software already exist for this?
03To use off-the-shelf software, how much would you change your processes?
04How many separate systems need to connect?

Think accounting, CRM, website, suppliers, spreadsheets and so on.

2 systems
05How important is full control and ownership of the system and data?
06How often do your requirements and processes change?
07Is this software a source of competitive advantage?
08With off-the-shelf software, how much manual work would remain?
09Are there unusual permissions, workflows or business rules?
10How operationally critical is this software?
11How many people will use it?
users
12Likely off-the-shelf subscription cost

Total across all users, per month. Leave blank if unsure.

£/ month

Recommendation

Hybrid approach likely

Custom software suitability45
Off-the-shelfHybridCustom

What's driving this

    Worth watching

      Suggested next step

      See a rough 3-year cost picture (optional)

      Add an indicative custom build budget to compare against your subscription figure above. This frames the decision. It is not a quotation.

      £build budget

      Not sure which approach is right?

      This gives you a steer, not a verdict. Describe your current systems and how the work actually flows, and I'll give you an honest view, including if the answer is to keep what you have.

      Talk it through
      01Context

      Buy when you can, build when it counts

      The honest default is to buy. Off-the-shelf software is cheaper up front, maintained by someone else and quick to adopt. If a product genuinely fits how you work, custom software is hard to justify.

      Custom starts to earn its place when your workflow is unusual, when you are stitching several systems together by hand, when off-the-shelf leaves a pile of manual work behind, or when the software is a real competitive edge rather than a commodity. Very often the sweet spot is ahybrid: keep the tools that work and build a focusedintegration orautomation layer around them.

      Whatever the score says, the real decision comes from looking at your actual process. If you want a second opinion,tell me how things work today.

      Insights

      Related reading

      All insights
      02FAQs

      Common questions

      How does the scoring work?

      Each answer feeds a weighted score out of 100 for how well-suited your situation is to custom software. Signals like a specialised workflow, many integrations, unusual rules and manual work left over push the score up. Signals like a standard workflow and good off-the-shelf options pull it down. Under 40 suggests off-the-shelf, 40 to 63 suggests a hybrid, and above that suggests custom is worth considering.

      Will it always tell me to build custom software?

      No, and that is the point. If off-the-shelf software fits your situation, the tool will say so. Custom software is a serious investment and it is not the right answer for most standard requirements.

      What is a hybrid approach?

      Keep the off-the-shelf tools that already do a good job, and build a smaller custom layer around them: integrations so they share data, automation for the manual steps, or a bespoke operational front end. You get most of the benefit of custom software without replacing everything.

      Is the cost comparison a quotation?

      No. The optional cost picture uses your own subscription figure and an estimated build budget with a simple assumption for ongoing running costs. It is there to frame the decision, not to price a project. A real figure needs the workflow scoped properly.

      What does custom software cost to run after it is built?

      Custom software is not a one-off cost. Budget for hosting, support, security updates and ongoing improvements. A common rough planning figure is somewhere around 15 to 20 percent of the build cost per year, though it varies with complexity.

      Talk through the right approach

      Tell me about your current systems and where the friction is. You'll get a straight answer on buy, build or hybrid, from the person who'd do the work.

      Discuss your situationSee how I work

      Or email me at josh@thackr.co.uk