Short answer: financial due diligence software has to do more than store documents or summarise a CIM. For a buyer, it must rebuild the seller's adjusted earnings from source records, test each quality of earnings adjustment, compute and track working capital against a peg, tie reported revenue back to invoices, bank statements and contracts, and attach a citation to every figure so a human can check it in seconds. The category is broad and the labels are loose, so the useful question is not "which product is best" but "which of these jobs does this tool actually perform, and can I see the evidence?"
This guide is written for search funds, independent sponsors and self-funded buyers. It is not accounting advice, and no software replaces a qualified accountant on a deal where the numbers decide the price.
What financial due diligence is trying to answer
Financial due diligence asks one question under several headings: is the profit the seller shows you real, repeatable and still there after closing? A buyer pays a multiple of earnings, so every dollar of overstated earnings is multiplied. Our guide to quality of earnings walks through the full analysis. Software only helps if it supports the pieces of that analysis, so start from the pieces.
| Workstream | The question | What the software must show |
|---|---|---|
| Quality of earnings | What does the business really earn once one-offs and owner costs are normalised? | Each adjustment listed, with the amount, the reason and the supporting document |
| Revenue tie-out | Does reported revenue match what customers were invoiced and what reached the bank? | A reconciliation from the income statement to invoices and bank deposits, with the gaps visible |
| Working capital | How much cash does the business need to run, and how does that compare with the proposed peg? | A monthly view of receivables, inventory and payables, and how the average is built |
| Debt and debt-like items | What obligations come with the business? | A list tied to contracts, loan statements and tax records |
| Customer and product concentration | Does a few accounts or products carry the profit? | Customer-level revenue from source data, not from a slide |
| Forecast and run rate | Is the trend supported by the last periods? | Period-by-period data that reproduces the headline figure |
If a product cannot show you which row of this table it covers, treat the marketing as a claim, not a capability.
Job 1: quality of earnings adjustments you can audit
The seller's adjusted EBITDA is a starting position. It usually contains add-backs: the owner's car, a family member on payroll, a one-off legal bill, a "non-recurring" repair that happens every year. Some add-backs are fair. Some are wishful.
Software that helps here should do three things:
- List every adjustment as its own line, with the amount and the reason, so you can accept, reject or ask a question about each one.
- Link each line to evidence: the payroll record, the invoice, the contract. An adjustment with no document is an opinion.
- Show the bridge from reported earnings to adjusted earnings, so a change to one adjustment flows through to the total without a hidden spreadsheet.
Be wary of any tool that outputs a single "normalised EBITDA" figure with no bridge. You cannot defend a number in a negotiation if you cannot show how it was built.
Job 2: working capital and the peg
Working capital is the area where small acquirers most often lose money without noticing. The peg is the agreed normal level of working capital, and the price is adjusted at closing if the delivered amount differs. Our explanation of the net working capital peg covers the mechanics.
For software, the requirements are practical:
- Monthly balances, not a single year-end snapshot, because a peg built from one date can be gamed by timing.
- Clear definitions. Which accounts count as working capital, and which are excluded as cash, debt or tax items? The tool should show the list, not hide it.
- A way to test the average. If the proposed peg is a twelve-month average, you should be able to see the months, spot seasonal swings and ask whether the last few months are unusual.
- Aged receivables and payables. A receivable that is a year old is not the same asset as one issued last week.
Software can compute all of this quickly. It cannot decide what the right definition is. That judgement stays with you and your adviser.
Job 3: revenue tie-outs to source documents
A tie-out proves that the revenue in the profit and loss statement is backed by evidence outside the profit and loss statement. In practice that means following the number down three steps: the reported figure, the invoices or contracts behind it, and the cash that arrived in the bank.
Things a good tool will let you check:
- Revenue by month from the ledger against revenue by month from invoices.
- Invoices against bank deposits, with unmatched items listed.
- Contract values and dates against what was recognised, especially for annual or multi-year deals recognised upfront.
- Credit notes, refunds and write-offs shown rather than netted away.
A gap does not prove fraud. Timing, tax treatment and currency can all explain differences. But an unexplained gap is a question for the seller, and good software turns a vague unease into a specific line you can send them.
Job 4: citations on every figure
This is the requirement that separates reading tools from storage tools. When software reads a deal document and produces a number, you need to see where it came from: the document, the page and the line. Without that, you have a new place for errors to hide.
The failure mode is well known. A model reading a long document can produce a clean, confident figure that is not in the text, or pull a number from the wrong table. The remedy is a rule applied to every claim: show the source, or drop the claim. We describe our approach in how to use Claude for due diligence, and it applies to any tool.
A quick test during a trial: ask the tool for five figures you already know from a document you have read. Check each citation against the page. If even one points to the wrong place, you know the cost of trusting the others.
Which category does your need fall into?
Products sold as due diligence software fall into different groups. The same word covers all of them, which is why comparisons confuse buyers.
| Category | What it does | Where it falls short for financial diligence |
|---|---|---|
| Virtual data rooms | Store and share documents with permissions and audit trails | Do not analyse the financials themselves |
| Accounting and QoE data platforms | Pull data from the target's accounting system and build tie-outs | Need access to the books, so they usually come late in a deal and may be run by an adviser |
| AI document readers | Read CIMs, financial statements and contracts and extract figures with citations | Work from the documents you give them, so they only check what is written |
| General AI chat | Answers questions about uploaded files | No built-in citation discipline unless you impose it |
| Spreadsheets | Flexible, familiar | Only as good as the person who built them, and hard to audit |
Most small deals use a mix. For a sense of the main named products and what each one does, read our guide to the best due diligence software, which dates the prices it quotes from each vendor's own pages.
What does financial due diligence software cost?
Cost is the second most common question after capability, and "m&a due diligence software cost" is a search many buyers run. The honest answer is that it depends heavily on the category.
- Virtual data rooms are often priced per project or per page, and many enterprise tools are sold through a quote rather than a public price list.
- Enterprise AI platforms are usually sold by demo and quote.
- Self-serve AI readers tend to publish prices, which makes them easier to compare.
We do not quote other vendors' prices here, because they change and we have not read them for this article. Our buyer's guide has a dated price comparison. For the services side of the bill, what due diligence costs breaks down typical adviser fees by deal size, and those fees are usually much larger than any software line.
Where Deal OS fits
Deal OS is our own product, so weigh this section with that in mind. It is a document reader: you upload a CIM and receive a brief in which every figure is traced to its source page, with contradictions between the CIM and the numbers flagged. It does not connect to a seller's accounting system, it is not a replacement for a quality of earnings report from an accountant, and it does not host a data room.
Its public pricing at getdealos.tech states that the first CIM is free, then $99 per CIM, or plans from $249 per month. Prices are in USD and exclude VAT. Check that page for current terms before you rely on those numbers.
A reasonable way to use a tool like this is as a first pass: run the CIM, read the cited brief, and use the flagged gaps to write your questions to the seller and your scope for an accountant. That can focus paid professional time on the places that matter. It does not remove the need for it.
A buyer's checklist for any financial diligence tool
Use these as pass or fail lines in a trial.
- Does it show each adjustment separately, with its evidence?
- Does it show monthly working capital and the definition behind it?
- Does it connect revenue to invoices or bank records, or say clearly that it cannot?
- Does every figure carry a citation you can open?
- Does it list what it could not find, rather than filling the gap?
- Can you export the work, so your files are yours if you stop paying?
- Is the price published, and does the page state what is excluded?
- Does the vendor say plainly what the tool does not do?
A tool that fails the last one is a warning in itself.
Frequently Asked Questions
What is financial due diligence software? It is software that helps a buyer test whether a target's reported financials are real. Depending on the product, that means reading financial statements and CIMs, building adjustments, tracking working capital or tying revenue to invoices and bank records. The term is used loosely, so check which of those jobs a given product performs.
What should financial due diligence software do for a small acquisition? At minimum it should list each earnings adjustment with evidence, show monthly working capital, link revenue to source documents and cite the page behind every figure. It should also tell you what it could not verify. It supports an accountant's work on larger deals, and does not replace it.
How much does M&A due diligence software cost? It varies by category. Virtual data rooms and enterprise AI platforms are often priced per project or by quote, while self-serve tools may publish prices. Our buyer's guide dates the prices read from vendors' own pages. Deal OS publishes its prices: first CIM free, then $99 per CIM, or plans from $249 per month, in USD excluding VAT.
Can AI replace a quality of earnings report? Not on a deal where the price depends on the numbers. AI can read documents quickly and flag gaps, but a quality of earnings report relies on access to the books and professional judgement. Many buyers use AI to prepare better questions before commissioning one.
How do I check that a tool's figures are right? Pick five figures you have already verified in a document, ask the tool for them, and open each citation. If any citation points to the wrong page or no page, treat every unverified figure with caution.
Is a virtual data room the same as due diligence software? No. A data room stores and shares documents. It does not analyse them. Many buyers need both: the room the seller provides, and a separate tool that reads what is in it.