Test data generator pricing looks simple until you line the plans up, because the leading tools don't charge on the same axis. Tonic Fabricate meters per generation turn, Mockaroo charges by the rows in a file, GenRocket sells a quoted annual license, and Seedfast bills a flat monthly rate that includes a pool of credits. Match those plans against each other and identical monthly figures buy incomparable things, since a bill that climbs with every CI run and one that never moves behave nothing alike at the same sticker price. The price question still deserves a straight answer, and that answer only makes sense read next to what each dollar actually buys.
Four test data generator pricing models at a glance
The table lines up all four on the axis that actually drives each bill, rather than on a single headline number; the full comparison hub has the feature-by-feature matrix behind the prices.
| Tool | Model | Entry paid price | Free option | Bill scales with | Source |
|---|---|---|---|---|---|
| Mockaroo | Rows per file, annual | $60/yr (Silver) | 1,000 rows/file | Dataset size | mockaroo.com |
| Tonic Fabricate | Credits + per-turn | $29/mo (Plus) | $5–10/mo credits | Generation volume | tonic.ai |
| GenRocket | Quote-gated license | ~$55K/yr (anchor) | None published | Projects and scope | genrocket.com |
| Seedfast | Flat monthly credits | $16/mo (Basic) | Free plan, no card | Credits per run | seedfa.st |
Mockaroo and GenRocket figures were verified June 2026 against the linked sources, Tonic Fabricate's pricing was rechecked in July 2026, and the Seedfast figures come from its own pricing page.
Mockaroo prices by the size of the file
Mockaroo pricing is the easiest of the four to reason about, because it turns on a single variable, the number of rows in one generated file. The free tier caps a file at 1,000 rows and allows 200 API requests a day, generous enough for one-off flat exports and fine for a demo or a fixture. Paid tiers raise the row ceiling, verified June 2026 against mockaroo.com/pricing. Silver at $60 a year lifts a file to 100,000 rows, Gold at $500 a year to 10 million rows, and Enterprise at $7,500 a year removes the cap. What that buys is volume rather than structure, so the bill tracks how large a dataset gets, not how tangled the schema is. One wide table of rows is cheap here. A Postgres schema of twenty related tables costs no more, because Mockaroo never models the relationships between them in the first place. Where row count is the wall you keep hitting, rows-per-file is a fair axis to pay on, and the Mockaroo alternative page picks up where that axis stops fitting.
Tonic Fabricate meters what you generate
Tonic Fabricate pricing works the opposite way, turning on how much you generate rather than how much comes out. It runs on generation credits plus token usage, checked July 2026 against tonic.ai/pricing. The free plan includes $5 a month in credits for a personal email, or $10 with a work email and every model unlocked, enough for light exploratory work and a real feel for the browser experience. Plus is $29 a month and folds in $25 a month of credits, after which pay-as-you-go kicks in at roughly $0.17 for a standard turn and about $0.37 for a complex, multi-table one. The structure matters more than the exact cents, because every run past your credits spends more of them, so the bill rises with usage. That suits occasional interactive sessions and gets harder to hold still once a generator lives inside CI and fires on every build, where per-turn cost compounds with build frequency instead of team size. The Seedfast vs Tonic Fabricate comparison runs the pricing math through in full.
GenRocket quotes an annual license
GenRocket sits in a different buying motion altogether. It publishes no public price list, no free tier, and no trial; the pricing page routes you to a quote request, so the number reaches you through sales rather than off a page. The one figure GenRocket publishes itself, on its value-for-money page (as of June 2026), anchors licensing at about $55,000 a year, framed there against legacy test data management it says can run past a million dollars. That tells you which tier you are shopping in. With a quote-gated tool the license is rarely the whole cost. The entry plan carries a twenty-project minimum, a fixed onboarding block, and a procurement lane you clear before the first row lands, so time-to-first-seed is measured in a sales cycle rather than minutes. For a team modeling scenario data across many databases, that overhead is the platform doing its job. For one Postgres schema that needs rows in CI, it is a lot of platform to buy, which the GenRocket alternative page takes apart.
Seedfast charges one flat monthly rate
Seedfast charges a flat monthly rate that includes a pool of credits, with no table or seed limits underneath, verified against Seedfast pricing in August 2026. Basic is $16 a month for $32 of credits and Premium $69 for $180, so every plan carries more credits than it costs. A credit is spent per seeding run rather than per row, and a full session on a 30-table schema runs about 60 cents, which puts Basic at roughly 50 runs a month and Premium at around 300. Evaluation runs free first, and stays free: the Free plan takes no card, never expires, and refills to $5 of credits each month, enough to seed a real schema in CI and watch it hold rather than poke at a toy. The bill is forecastable by construction, since nothing scales with build frequency or dataset size. The honest limit is that Seedfast is Postgres-only, so a multi-engine shop is better served elsewhere. Inside its lane, seeding a Postgres database in CI, the cost is a fixed line item you can budget once and forget.
How to run a real cost comparison
Comparing sticker prices tells you little here, because the axes differ. A more honest estimate takes how you will actually use the tool and pushes it through each model. Count the seeds or generation runs you expect in a typical month, multiply by the cost each model assigns to a run, and the shapes separate quickly. A rows-per-file tool charges the same whether you generate once or fifty times, so its cost stays flat but capped by volume. A per-turn tool multiplies its per-run price by your run count, so a generator that fires on every CI build carries a bill that grows with build frequency. A quote-gated license is fixed but large, and a flat monthly plan is fixed and small, independent of run count altogether. Forecastability is the quiet variable most pricing pages skip. A cost you can predict a year out is easier to defend in a budget than a lower one that swings with usage. Vendors also reprice over time, so confirm the current figure at each source before you commit.
Frequently asked questions
How much does Mockaroo cost?
Mockaroo is free for files up to 1,000 rows with 200 API requests a day, then paid by file size on annual plans, verified June 2026 at mockaroo.com/pricing. Silver is $60 a year for 100,000 rows per file, Gold $500 a year for 10 million, and Enterprise $7,500 a year for unlimited rows and users. The bill follows dataset size, so a larger file costs more while schema complexity costs nothing.
How much does Tonic Fabricate cost?
Tonic Fabricate runs on generation credits plus per-turn usage, checked July 2026 at tonic.ai/pricing. The free plan includes $5 a month in credits for a personal email or $10 for a work email with full model access, Plus is $29 a month with $25 a month in credits, and beyond credits you pay roughly $0.17 per standard turn and $0.37 per complex turn. Because it meters generation, the bill scales with how much data you produce, which makes a CI generator that runs on every build the case to model most carefully.
Which test data generator is cheapest for CI use?
Cost in continuous integration tracks how often the pipeline fires, because a generator wired in after migrations runs on every build. Tonic Fabricate's per-turn meter therefore climbs with build frequency (as of July 2026, tonic.ai/pricing), and Mockaroo's rows-per-file ceiling turns into repeated export-and-import work at the same cadence (as of June 2026, mockaroo.com/pricing). Seedfast charges the same plan price whether the pipeline seeds once a week or on every commit, and a run draws from the credits the plan already includes, roughly 60 cents on a 30-table schema, so the invoice is known before the month starts. Which of the three comes out cheapest still depends on your build volume, so estimate runs per month against each model rather than trusting a headline price.
How much does Seedfast cost?
Seedfast charges a flat monthly rate that includes a pool of credits, and a run draws from that pool by how much data it generates rather than by row or by token, verified at Seedfast pricing in August 2026. The free plan takes no card, never expires, and includes $5 of credits a month; Basic is $16 a month for $32 of credits and Premium $69 for $180. Plans differ by how many credits they include, not by rows, tokens, or table counts, and there are no table or seed limits on any of them.
Match the pricing model to how you work
The sharper question is not which number is smallest but which axis matches how you work. Flat, occasional test data is exactly what Mockaroo's row-based annual plans are priced for (as of June 2026, mockaroo.com/pricing). Generating interactively in a browser, where AI-assisted iteration is most of the value, suits Tonic Fabricate's credit model, with the caveat that CI usage compounds it (as of July 2026, tonic.ai/pricing). GenRocket's quoted license is built for governing test data across many systems at enterprise scale, and that is the scope it expects you to have (as of June 2026, genrocket.com).
And where the job is seeding a Postgres database in CI on a cost you can defend in a budget a year out, Seedfast is the one that stays still, because its plans are flat monthly with a pool of credits included rather than a meter that moves with the pipeline. Evaluating it costs nothing, since the free plan takes no card, refills $5 of credits each month, and does not expire.