Predictefy vs Marketlens: Prediction Market Data Compared (2026)

Product details and monthly prices checked on October 27, 2026.

How do Predictefy and Marketlens compare?

Why choose Predictefy for a cross-venue strategy?

A Polymarket strategy can reveal a second question: how did the equivalent contract trade on Kalshi or another venue? Predictefy provides one catalog and schema for that investigation. Cross-venue matching helps you find the related listings while retaining each venue's contract identity.

You can use the same integration to inspect current prices, request historical records and subscribe to updates. Observation timestamps and provenance help the application distinguish a recorded value from a new market update.

For the next stage, Predictefy supports paper trading and client-signed execution for supported venues. That gives the developer a practical route from a research notebook to a monitored application. Its Pro arbitrage feed checks requested depth, venue fees and resolution equivalence when qualifying a candidate.

What does Marketlens offer for Polymarket backtesting?

Marketlens centers its product on historical Polymarket order books. Its Python SDK provides strategy callbacks and a backtest engine with configurable execution assumptions. The published examples model simulated fills, fees and latency.

Its catalog spans recurring crypto markets, sports, politics, weather and other event categories. The site describes continuous tracking of recurring product families and automatic admission of other events that meet a trading-volume threshold. Check the catalog entry for the series you need before assuming coverage.

Marketlens also provides an MCP server and downloadable data. Those interfaces can be useful if your existing research environment already works with Python and local files. The specific comparison is whether you want a Polymarket replay environment or a cross-venue integration that also supports ongoing market monitoring.

What should a credible order-book backtest measure?

Use a fixed market, date range and decision rule. Keep the simulated order's arrival time separate from the time the strategy observed the book. An order generated from a snapshot cannot automatically receive the best fill that appeared in that same snapshot.

Inspect queue position, partial fills, fees and how the model handles missing data. Millisecond timestamps describe the dataset's time precision. They do not establish the live latency you would obtain from a trading connection.

For Predictefy, request the exact captured range and inspect provenance and quality fields. For Marketlens, confirm the series and market dates in its catalog. Compare a busy period with a quiet one and rerun the model with less favorable fill assumptions. A result that depends on optimistic execution needs more investigation.

How do the plans compare?

Predictefy Free includes 25,000 credits each month for evaluation. Builder is $48.88 a month with 250,000 credits. Pro is $149 with 2,000,000 credits and adds history replay, arbitrage and the price-gap feed. Commercial use is an Enterprise contract term. Check the pricing guide for your workload.

Marketlens Free lists a one-time allowance of 2M data rows and access to markets open within the last seven days. Pro is $39 a month with 5B data rows per month and access to the archive since March 2026. Scale is $199 with 50B rows per month. These are data-row allowances, so compare them with the number of records your queries return.

Keep archive eligibility separate from capture. A paid plan opens a date window; your chosen market still needs usable records for that period.

How should you test a Marketlens alternative?

1. Choose one Polymarket strategy and record its data, timing and fill assumptions.
2. Use Predictefy matching to identify comparable contracts on other venues.
3. Request sample historical ranges and check settlement terms, gaps and timestamps.
4. Run a paper-trading evaluation and compare its behavior with the historical simulation.

Start with the history guide and a Predictefy evaluation key. Use the same contract definitions throughout the test.

Frequently Asked Questions