Frequently Asked Questions

Answers to the most common questions from new Quantlens users.

Backtesting

My strategy shows 500% total return — is that realistic?

Probably not for live trading. Very high returns in a backtest almost always indicate one of three things:

  1. Overfitting — the parameters were tuned too precisely to historical data and won’t hold in the future.

  2. Survivorship bias — the dataset only includes stocks that survived, excluding companies that went bankrupt.

  3. Look-ahead bias — the strategy inadvertently “saw” future data (check your offset values).

A realistic Sharpe Ratio is 0.8–1.5 for a robust strategy. A Sharpe above 2.5 is worth investigating carefully.

Why does my backtest show 0 trades?

Common causes:

  • The Config Block block’s start/end dates don’t overlap with available data.

  • The entry condition is never true — check that your indicators produce valid values (e.g. RSI needs at least period + 1 bars of data before it outputs a number).

  • The Trading Loop or On Interval blocks are missing or incorrectly nested.

  • Stop-loss is set very low (e.g. 0.001), causing immediate exit before any meaningful holding period.

Why is my backtest much worse than the example strategies?

Possible reasons:

  • Date range — some periods are genuinely better for certain strategies. Try extending the test range.

  • Commission and slippage — even small fees compound over hundreds of trades. Try setting commission to 0 temporarily to isolate its impact.

  • Too many slots — more positions = more diversification = lower individual position sizes = less impact from any single win.

  • Mean-reversion in a trending market — RSI strategies underperform during strong bull markets where RSI stays elevated.

Does a longer backtest period always give more reliable results?

Longer is generally better — more trades means more statistical significance. Aim for at least 100–200 completed trades before trusting a metric. However, very old data (pre-2000) may include market regimes that no longer exist.

My strategy wins 30% of the time — is it broken?

Not necessarily. Trend-following strategies typically have low win rates (30–45%) but profit because the average winning trade is much larger than the average losing trade. Check the Profit Factor — if it’s above 1.5, the strategy is extracting value even with a low win rate.

Results & Metrics

What’s a good Sharpe Ratio?

Sharpe

Assessment

< 0

Losing money risk-adjusted. Don’t trade this.

0 – 0.5

Weak. Unlikely to survive real trading costs.

0.5 – 1.0

Acceptable for some systematic strategies.

1.0 – 2.0

Good. Worth further investigation.

> 2.0

Excellent — but verify it’s not overfit.

What’s a good Max Drawdown?

There is no universal answer — it depends on your personal risk tolerance. A drawdown of -20% means your $10,000 portfolio temporarily fell to $8,000 before recovering.

As a rough guide:

  • < 15% — Conservative. Suitable for most investors.

  • 15–30% — Moderate. Requires discipline to hold through.

  • 30–50% — Aggressive. Very difficult psychologically.

  • > 50% — Extremely high risk. Most real traders would quit before recovery.

Warning

Backtested drawdowns are usually underestimates — live trading often produces deeper drawdowns due to execution slippage, bid-ask spreads, and illiquidity.

The equity curve rises steadily then crashes at the end — why?

The strategy likely over-concentrated in a specific sector or period. Common causes:

  • No market filter — the portfolio was fully invested during a market crash (2008, 2020, 2022).

  • Small out-of-sample period — the last year of data is always unseen by the optimizer; performance degrades.

Add Index Value > SMA(200) as a market filter to exit all positions when the broad market is in a downtrend.

Sortino Ratio is higher than Sharpe — what does that mean?

It means your strategy’s losses are actually small and infrequent — most of its volatility is on the upside. This is a good sign. Sortino penalises only downside volatility, so a Sortino > Sharpe indicates the strategy has an asymmetric return profile (many small losses, few large wins).

Strategy Building

Can I use multiple indicators together?

Yes — connect them with AND/OR logic blocks. For example: RSI(14) < 30 AND MACD histogram > 0 AND Index > SMA(200)

Each additional condition tightens your filter and reduces the number of trades. More conditions = fewer but (potentially) higher-quality trades.

What’s the difference between eod and sod execution?

  • eod (end of day) — the trade executes at the closing price of the current bar.

  • sod (start of day) — the trade executes at the opening price of the next bar.

eod slightly overstates performance (you can’t actually trade the exact close in real time). sod is more realistic but adds one day of slippage.

How does the Slots setting affect my strategy?

Slots is the maximum number of open positions at once. The portfolio allocates 1 / slots to each position equally.

  • 5 slots: each position = 20% of portfolio. More concentrated, higher risk/reward.

  • 20 slots: each position = 5% of portfolio. More diversified, smoother equity curve.

More slots generally reduces Max Drawdown but also reduces peak returns.

Why should I use the Cooldown Filter?

Without it, a stock stopped out this week immediately becomes eligible for re-entry next week. This can trap you in a “death spiral” — buying a deteriorating stock, getting stopped, buying again, getting stopped again.

The Stock Cooldown Filter blocks stocks for N days after a stop-out, forcing the strategy to find different positions.

What does the Offset parameter do on indicators?

Offset shifts the indicator value back in time.

  • Offset = 0 → today’s RSI value.

  • Offset = 1 → yesterday’s RSI value.

Use offsets to compare values across time — e.g. RSI(14) Offset=0 > RSI(14) Offset=1 is true when RSI is rising.

Account & Plans

How many backtests can I run per month?

Plan

Monthly backtest limit

Bronze

50

Silver

200

Gold

Unlimited

The counter resets on the 1st of each month. See Plans & Billing for full plan details.

Can I try the platform before paying?

Yes — new accounts automatically receive a free Silver trial. No credit card is required to activate it.

I accidentally deleted my strategy — can I recover it?

Use the Snapshot feature to save checkpoints of your workspace before making major changes. If no snapshot was saved, the workspace cannot be recovered.

Make it a habit: click Save Snapshot before editing any strategy you care about.

The optimizer ran but all results look the same — why?

If all parameter combinations produce similar results, it usually means:

  1. The strategy’s performance doesn’t depend heavily on those parameters (robust — a good sign).

  2. The parameter range is too narrow. Try wider ranges (e.g. 7, 14, 21, 28 for RSI instead of 13, 14, 15).

  3. The strategy has too few trades to distinguish between parameter sets reliably.

Troubleshooting

The page loads but the canvas is blank

  • Hard-refresh the browser (Ctrl+Shift+R / Cmd+Shift+R).

  • Clear your browser cache.

  • Try a different browser (Chrome or Firefox recommended).

My results disappeared after refreshing the page

Results are tied to the current workspace session. To save results permanently, use Export PDF or Save Snapshot before closing the tab.

The backtest runs for a very long time

Long run times are usually caused by:

  • A very large date range (20+ years) combined with short intervals (1d).

  • Heavy use of multiple indicators with long periods (e.g. SMA(500)).

  • Complex nested conditions evaluated on every single bar.

Try reducing the date range first, then simplify the strategy if needed.

Still have questions? Contact support at hello@quantlens.io or open a thread in the Community forum.