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10tests100,000spins open data closed rig 18+
LAB · DOC 02 updated 2026-09-06 7 sections

About the lab

Slotester Lab measures slot games on their official demo servers and publishes what the logs say. The rig plays, the editor checks, the data stays open. This page is who is behind it, how it is run and how it is paid for.

Slotester Lab bench at night with a test device, an open checklist notebook and a monitor showing a balance curve
The lab bench: the rig, the editor notebook and one balance curve.

What the lab is

measurement first, opinion second

Slotester Lab does one thing: it runs slot games on their providers' official demo servers, records every server response, and publishes what the numbers say. A review here is not an impression of a game after an evening of play. It is a report on a fixed procedure: ten thousand logged rounds, fifty bonus purchases where the game sells them, one recorded session, and a set of statistics computed from the log with their uncertainty attached.

The testing is done by software. The judgement of what the numbers mean, and the responsibility for what is published, stays with a human editor. Both facts are printed on every page, because the reader should know which parts were measured and which were written.

Three parts

rig · editor · open data

The rig

A test harness written in Python. It speaks the game server's own protocol, so a run is 10,000 real server rounds rather than a simulation, and it drives a real Chrome window for screenshots and video. The rig also drafts the first version of each review from the log.

closed source

The editor

One person reads every figure in the draft against the log, checks the screenshots and the video, rewrites what is unclear and decides whether the run is fit to publish. Nothing goes live on the rig's word alone.

human sign-off

Open data

Every review links to its rounds file with a SHA-256 checksum and explains how the numbers were computed. Anyone can recompute the RTP, the hit rate or the biggest round from the same file.

downloadable logs

Principles

the rules the lab holds itself to
  1. 01No money from game studios. Providers do not pay for tests, cannot commission them and are not told in advance which game is next.
  2. 02Numbers are never edited. If a run looks odd, it is re-run or investigated, and the reason is written into the review. A measured 80% stays 80%.
  3. 03One sample, said out loud. Every review carries a confidence interval and the sentence that a different session can land elsewhere.
  4. 04Same procedure for every game. Same spin count, same purchase count, same bet logic, same checks. Comparisons across reviews mean something because the method does not move.
  5. 05Open data, closed rig. The logs are public; the software that produces them is not, because a published rig is a rig that can be gamed.
  6. 06No invented people. Reviews are signed by the lab, not by fictional experts with stock-photo faces.

Numbers to date

live from the published tests
  • slots tested 10 2026-09-03 to 2026-09-04
  • rounds logged 100,000 base series only
  • bonus buys 350 7 games sell the feature
  • natural bonuses 344 triggered without buying
  • mean measured RTP 90.6% declared average 96.47%
  • hit rate range 13% – 43% longest dry run 54 spins
SlotTestedRTP declared → measured95% intervalBuysLog
Sweet Bonanza 1000 2026-09-04 96.5 → 92.5% 80.8–104.2% 50 · 1.19x 2c1da033ff…
Gates of Olympus 1000 2026-09-04 96.5 → 115.9% 86.5–145.4% 50 · 1.05x 1dc201c36a…
Fruit Party 2026-09-04 96.5 → 87.5% 67.3–107.7% 50 · 0.83x 0ab72c346b…
Wolf Gold 2026-09-04 96.0 → 98.4% 87.8–109.1% no buy c709c353e7…
Sugar Rush 2026-09-04 96.5 → 90.8% 74.7–106.9% 50 · 1.06x 85ecc76e70…
Starlight Princess 2026-09-04 96.5 → 88.2% 73.4–103.0% 50 · 1.07x 6825a0bf01…
The Dog House 2026-09-04 96.5 → 83.6% 67.3–99.9% no buy 02dd7ba914…
Big Bass Bonanza 2026-09-03 96.7 → 81.2% 66.8–95.6% no buy 260d0a41d2…
Sweet Bonanza 2026-09-03 96.5 → 87.3% 78.5–96.1% 50 · 0.86x 4ea1621c0f…
Gates of Olympus 2026-09-03 96.5 → 80.2% 68.6–91.8% 50 · 0.77x b50ddd3aa6…

Timeline

how the lab got here
  1. Rig 0.1.0 and the first review

    The harness learns the Pragmatic Play protocol end to end: session, spins, cascades, free spins, purchases, media capture. Gates of Olympus is the pilot review.

  2. The standard is set

    Ten thousand spins and fifty purchases per game replace the shorter pilot runs. The pilot is re-run to the new standard before anything else is added.

  3. Ten games in one night

    Cluster games, respin features and 1000x editions force protocol fixes; a balance-reconciliation check is added and applied to every run retroactively. Ten reviews are live by morning.

  4. The register and these pages

    Reviews are cross-linked through a lab register, and the documentation pages are rewritten around live data instead of boilerplate.

How it is funded

the short version

The site can carry partner links to online casinos under the demo of a game. If a reader signs up through such a link, the lab may earn a commission. That is the only revenue model. Partner links never touch the measurements, the order of reviews or the wording of a verdict, and they are marked as sponsored wherever they appear.

Read the affiliate disclosure

Why one name

no personas, one responsible editor

Reviews are published under the lab's name rather than under invented reviewer profiles. The measurements are the same whoever presses the button, and a fictional byline would add a face without adding accountability. Corrections, questions and requests all go to the same place, and the editor who signs off on a review is the one who answers for it.

Contact the lab