Choose CNC quoting software by testing whether your shop can inspect, correct and explain the estimate. Begin with a part you have already quoted. A low total or a fast upload alone does not tell you whether the result includes the work you must deliver.
This is Kostira’s proposed evaluation method, internally reviewed against the current product scope. It is not an independent vendor ranking or an externally reviewed manufacturing benchmark. Use the same checks for Kostira and every other candidate.
1. Decide which workflow you need
These categories help you define the trial; products can combine several of them. Confirm the actual features and commercial terms of each candidate.
| Your immediate task | Category to investigate | What the trial must establish |
|---|---|---|
| Maintain your own costing formulas | Spreadsheet or estimating template | Another estimator can understand the inputs, formulas and revisions |
| Bring CAD geometry into an editable estimate | CAD-assisted quoting software | The imported part is correct and shop assumptions can be reviewed and changed |
| Let customers submit RFQs or place orders | Quoting portal | Submission, review, approval and customer communication fit your process |
| Connect quoting to production records | ERP or MES with estimating | Quote data moves into the required purchasing, planning or production workflow |
If your main problem is transferring geometry into a spreadsheet, start by testing that handoff. If the problem is scheduling approved work, include the downstream workflow in the trial. A long feature list does not establish either result.
2. Give every candidate the same inputs
Prepare a comparison pack with an authorized STEP model, the matching drawing revision, material and stock requirements, quantity, shop rates, outside-process requirements and inspection scope. Keep your approved reference estimate alongside it. Record the trial date, software version where shown, and any starter values you replace.
STEP can carry more than shape, including product and manufacturing information. The NIST STEP File Analyzer documentation distinguishes geometry, PMI and validation information. Check what your file contains and what each importer actually reads; do not assume a visible model means the drawing requirements entered the estimate.
If an input is unsupported, record the gap and the manual work required. Changing the test part to suit each tool prevents a like-for-like comparison.
3. Use a comparison sheet
Copy these rows into your worksheet. Add a result column for each candidate and retain the corrected estimate or export as evidence. Choose pass, requires manual work, blocked or not tested for each row. Treat a blocked requirement your shop considers essential as a decision point, even if other rows pass.
| Check | Test to perform | Evidence to keep |
|---|---|---|
| Geometry | Confirm imported dimensions and units against the drawing | Dimensions checked; any import correction |
| Purchased stock | Compare blank size and material quantity with your reference | Allowances, waste and purchasing assumptions |
| Operations | Review the sequence, setups and separately costed work | Added, removed or corrected operations |
| Time and rates | Replace examples with your documented shop inputs | Editable fields, units and any hidden assumptions |
| Quantity | Repeat the estimate at two batch sizes | Fixed and per-part costs before and after the change |
| Selling price | Separate manufacturing cost from the commercial decision | Currency, margin or markup definition and exclusions |
| Export | Open the PDF or spreadsheet and reconcile it with the reviewed estimate | Matching lines and totals; customer-facing versus internal information |
| Revisions | Change one assumption and export again | An understandable revised estimate and document |
| File handling | Review current access, retention and deletion information | Requirements still needing an answer before customer files are used |
| Handoff | Have another estimator explain the result | Missing context, manual steps and unresolved questions |
Agree your required outcomes before seeing the results. For example: “We must be able to correct a setup, retain our shop rate and reconcile the export.” Keep optional conveniences separate so they do not conceal an essential gap.
4. Challenge a matching total
The following is a synthetic arithmetic example, not a test result from Kostira or another vendor. It illustrates why matching one quote is insufficient.
Suppose your reference allocates EUR 160 once per batch and EUR 26 per part. A second hypothetical model allocates no batch cost and EUR 42 per part. Both reach EUR 420 for ten parts:
| Model | Fixed cost per batch | Variable cost per part | Cost for 10 parts | Cost for 100 parts |
|---|---|---|---|---|
| Reference assumptions | EUR 160 | EUR 26 | EUR 420 | EUR 2,760 |
| Different assumptions | EUR 0 | EUR 42 | EUR 420 | EUR 4,200 |
Here, batch cost = fixed cost + quantity × variable cost. The illustration assumes one batch, unchanged rates and process, and no additional setups, scrap, minimum supplier charges or capacity changes. It is not a promise that a real job scales this way.
The first total hides a disagreement about cost allocation. Changing quantity exposes it. Reconcile the assumptions before deciding which model fits your process. The worked CNC quoting guide shows how the reference’s setup and per-part inputs are built.
5. Measure the work needed to reach a usable quote
Record account setup, processing wait, active estimating, corrections and final review separately. Keep a note of what needed correction, not just the stopwatch total. Set a trial time limit that reflects your workflow; do not accept an unsupported vendor speed claim as your baseline.
Before comparing estimates, align scope, currency, quantity, material prices, rates and the treatment of risk. If totals still differ, inspect the lines. One matching part does not establish performance across unfamiliar geometries, materials or processes. Expand the trial to representative work before relying on it for customer quotes.
6. Where Kostira fits
Kostira is a browser-based STEP-to-estimate workflow with editable shop assumptions and PDF/XLSX output. It accepts .step and .stp. The current offer is a free open beta without a payment card. The app interface is English; workspace currencies are PLN, EUR, USD, GBP, CZK, MXN and CAD. Review starter rates before using them.
The estimator remains responsible for requirements outside the model, process choices, time assumptions and the final quote. Kostira publishes no validated accuracy percentage. An XLSX export is an output to inspect, not a promise to reproduce your existing workbook. Read the spreadsheet comparison and current file-handling guidance for those parts of your evaluation.
Start with the STEP workflow, then try one previously quoted part. Your first useful outcome is an estimate you can explain and reconcile with its export.
Sources and review scope
- NIST: STEP File Analyzer and Viewer — the scope of STEP data, PMI, validation information and file analysis. This source does not endorse Kostira or the evaluation checklist.
- Kostira workflow, beta terms and security guidance — product statements checked on October 1, 2026.
- How to quote CNC parts — assumptions behind the linked synthetic costing example.
The comparison method and decision criteria are editorial recommendations from the Kostira team. No competitor scores, customer outcomes or independent expert endorsement are claimed.