New here? Cashflow Engine backtests SPX 0DTE options strategies and puts them in a Strategy Browser — a searchable table where you filter by strategy type, spread width, premium, stop-loss and entry time, then compare what each one did. It holds 245,250 of them — but not 245,250 different ideas. They are 14 strategy variants, each measured across a grid of parameters. This page is the map to those 14: what separates them, which ones get confused with each other, and how to read the IDs that name them.
Two of the three names are borrowed, and worth crediting: MEIC is attributed to Tammy Chambless, METF to Dan Yaklin. Ratio spreads are a standard options structure with no single originator. We did not invent the vocabulary — we measure it.
What is the difference between MEIC, METF and ratio spreads?
All three sell defined-risk credit spreads on SPX 0DTE options at several entry times a day. They differ in how they take a side. MEIC takes both sides equally and stays neutral. METF takes one side per entry, chosen by an EMA gate. A ratio spread takes both sides but makes one of them bigger — the lean comes from size, not from a filter.
| MEIC | METF | Ratio | |
|---|---|---|---|
| Full name | Multiple Entry Iron Condor | Multiple Entries Trend Following | Ratio spread |
| Attributed to | Tammy Chambless | Dan Yaklin | Standard structure — no single originator |
| Sides per entry | Put and call | Put or call | Both — one big, two small |
| How direction is chosen | It isn't — neutral | An EMA gate decides, per entry | By structure — the big side is the lean |
| Trend filter | None | Minute-EMA crossover gate | None |
| Variants | 3 | 9 | 2 |
All three share the same building block: a credit spread — two options, one sold and one bought further out, collecting a net credit with a maximum loss you know before you enter. And all three open several entries staggered across the session rather than one position a day; that is the "multiple entries" in the first two names. Each entry is its own trade with its own strikes, credit and stop, not an adjustment to something already running.
What strategy variants exist?
Fourteen. Three MEIC variants (both sides, put-only, call-only — none filtered), nine METF variants (three EMA pairs × both/put-only/call-only, all filtered), and two ratio structures. Three dials generate all of them: which sides you sell, whether a filter decides, and whether the two sides are the same size.
Understand meic_both and you have the map. Everything else removes a side, adds a filter,
or changes the size ratio between sides.
MEIC — no filter, both sides
meic_both is the anchor: several entries across the day, each selling both sides. The
other two are meic_both with one side removed — and still unfiltered, which is the word that
matters: meic_put sells its put spread on a deep-red down day too. Nothing stops it.
| Variant | Sides per entry | Filter |
|---|---|---|
meic_both | Put + call | — |
meic_put | Put only | — |
meic_call | Call only | — |
METF — an EMA gate picks the side
The gate compares a fast and a slow exponential moving average of the index at the moment of entry. Put spreads open when the fast EMA is above the slow one (an uptrend); call spreads when it is below (a downtrend). You sell the side the market is moving away from — and because those two rules are strict opposites, exactly one side can open per entry.
The three pairs — 5/20, 5/40, 20/40 — differ only in how twitchy the filter is. put_* and
call_* are the same strategies restricted to one side.
| Variant | Sides per entry | Gate |
|---|---|---|
metf_520 · metf_540 · metf_2040 | Put or call | EMA 5/20 · 5/40 · 20/40 |
put_520 · put_540 · put_2040 | Put only | the uptrend entries of the pair |
call_520 · call_540 · call_2040 | Call only | the downtrend entries of the pair |
How the gate behaves minute by minute, and what all three pairs do across every entry slot, is the subject of the METF deep-dive.
Ratio — both sides, deliberately unequal
A ratio spread keeps both sides on, then makes one of them dominant: one big credit spread
against two smaller spreads on the opposite side. ratio_1p2c is one big put spread plus
two small call spreads; ratio_1c2p mirrors it.
The two sides are premium-balanced — the single big leg collects about what the two small legs collect together. So the lean is not in the credit, it is in the shape: one side is wide and singular, the other narrow and doubled. Unlike METF, nothing filters the entry; unlike MEIC, the two sides are not the same size.
| Variant | Structure | Filter |
|---|---|---|
ratio_1p2c | 1 big put spread + 2 small call spreads | — |
ratio_1c2p | 1 big call spread + 2 small put spreads | — |
Why 14 variants become 245,250 strategies
A variant is a rule, not a trade. metf_520 says "sell one side per entry, gated on the
5/20 EMA" — it does not say how wide, for how much credit, with what stop, or when. Fill
those in and you get a strategy you could actually place: METF_W150_SL95_P3-0_E0954_520.
The Strategy Browser holds every filled-in combination, backtested separately.
The axis that matters most there is entry time: 109 of those combinations differ only in when the entry happens. Most published 0DTE research picks one entry time and reports it. A single point is a different object from the whole surface — and comparing across all 109 is the only way to tell whether a result is a property of the strategy or a property of the clock.
The two ratio structures run a narrower grid than the other twelve, because premium-balancing fixes the relationship between the big and the small side and rules out most free combinations.
Which variants are easy to confuse?
meic_put and put_520. Both mean "puts only" and both sell the identical option
structure, but meic_put trades every entry regardless of trend while put_520 trades only
when the EMA gate says uptrend. Same name shape, materially different exposure.
meic_put | put_520 | |
|---|---|---|
| When does it sell? | Every entry, always. No filter. | Only when the fast EMA is above the slow. |
| On down days? | Fully in anyway. | Does nothing at all. |
| Trade count | Higher | Lower — but filtered |
If you trip anywhere, it is here. The meic_* single sides are unfiltered halves of an
iron condor. The put_* / call_* variants are gated halves of a METF. The words are
nearly identical; the risk profile is not.
How do you read a strategy ID?
Every ID in the Strategy Browser follows one pattern: family, width, stop-loss, premium,
entry time, then an optional EMA pair and an optional side. METF_W150_SL95_P3-0_E0954_520_C
is a METF call-only spread, 150 wide, 95% stop, targeting 3.00 premium, entered at 09:54,
gated on the 5/20 EMA pair.
| Segment | Meaning |
|---|---|
METF | Family — MEIC, METF, or a ratio (R1P2C / R1C2P) |
W150 | Spread width, 150 points |
SL95 | Stop-loss at 95% of the credit collected |
P3-0 | Premium target 3.00 — the hyphen is the decimal point |
E0954 | Entry at 09:54 |
520 | EMA pair 5/20 — METF only; MEIC never carries one |
_C / _P | Call-only / put-only. Absent means both sides. |
Two notes that save a misreading. Strikes are chosen by premium, not delta — P3-0 means
"target 3.00 credit", not "take 30 delta". And a ratio ID describes its big leg: the width
and premium belong to the single dominant spread, while the two small legs on the other side
are derived from it — half the premium, and a narrower width that is mapped, not simply
halved.
All 14 at a glance
| Variant | Sides per entry | Trend filter | Family |
|---|---|---|---|
meic_both | Put + Call | — | MEIC |
meic_put | Put only | — | MEIC |
meic_call | Call only | — | MEIC |
metf_520 | Put or Call | EMA 5/20 | METF |
metf_540 | Put or Call | EMA 5/40 | METF |
metf_2040 | Put or Call | EMA 20/40 | METF |
put_520 | Put only | EMA 5/20 · uptrend | METF |
put_540 | Put only | EMA 5/40 · uptrend | METF |
put_2040 | Put only | EMA 20/40 · uptrend | METF |
call_520 | Call only | EMA 5/20 · downtrend | METF |
call_540 | Call only | EMA 5/40 · downtrend | METF |
call_2040 | Call only | EMA 20/40 · downtrend | METF |
ratio_1p2c | 1 big put + 2 small calls | — | Ratio |
ratio_1c2p | 1 big call + 2 small puts | — | Ratio |
How we counted this
245,250 is a count of the distinct backtested strategies in the Strategy Browser — every combination of variant, width, stop-loss, premium target and entry time that carries a result. It counts strategies, not performance.
- Data: our SPX 0DTE backtest dataset, built on second-level data. Underlying strategy P&L series are modeled (not actual) fills, net of commissions and modeled slippage — though this page cites none of them.
- What counts as one strategy: one distinct combination of variant, width, stop-loss, premium target and entry time. Counted directly from the Browser's own data, per variant — no estimate, no rounding.
- Counts, not returns. Nothing on this page states what any variant or configuration earned, and nothing here should be read as suggesting what any of them would earn.
Frequently Asked Questions
- What is the difference between MEIC and METF?
- MEIC (Multiple Entry Iron Condor) sells both a put spread and a call spread at every entry and is market-neutral. METF (Multiple Entries Trend Following) sells exactly one side per entry, chosen by a minute-EMA crossover gate, making it directional. Both use the same defined-risk vertical spreads on SPX 0DTE.
- How is a ratio spread different from an iron condor?
- An iron condor sells a put spread and a call spread of equal size, so it leans neither way. A ratio spread sells one big spread on one side against two smaller spreads on the other, premium-balanced across the two — so it takes a directional lean through its shape rather than through a filter or an unequal credit.
- How many strategy variants are there?
- Fourteen across three families: three MEIC variants (both sides, put-only, call-only — none filtered), nine METF variants (three EMA pairs × both/put-only/call-only, all gated), and two ratio structures.
- How many SPX 0DTE strategies are in the Strategy Browser?
- 245,250. Each of the 14 variants is measured across a grid of spread widths, premium targets, stop-loss levels and 109 intraday entry times, so one variant becomes tens of thousands of fully specified, individually backtested strategies.
- What is the difference between meic_put and put_520?
- Both sell only put spreads and both use the identical option structure, but meic_put is unfiltered — it trades every entry regardless of trend — while put_520 only trades entries where the 5/20 EMA gate signals an uptrend. Same words, materially different exposure.
- What do the segments in a strategy ID mean?
- Family, width, stop-loss, premium target, entry time, then an optional EMA pair and an optional side suffix. In METF_W150_SL95_P3-0_E0954_520_C: METF family, 150-wide spread, 95% stop-loss, 3.00 premium target, 09:54 entry, 5/20 EMA pair, call side only. Strikes are selected by premium, not delta.
Terms & Definitions
- MEIC
- Multiple Entry Iron Condor — an SPX 0DTE strategy family that opens several iron condors staggered across the trading day instead of a single entry, selling both a put and a call spread at each one, with no trend filter. Attributed to Tammy Chambless.
- METF
- Multiple Entries Trend Following — an SPX 0DTE strategy family that opens several single-side credit spreads staggered across the trading day, with a minute-EMA crossover gate deciding, per entry, whether that entry sells a put spread or a call spread. Attributed to Dan Yaklin.
- Ratio spread
- A credit structure that keeps both sides on but makes them unequal: one big spread on one side against two smaller spreads on the other, premium-balanced across the two, so the directional lean comes from the shape rather than from a filter.
- Credit spread
- Two options on the same side, one sold and one bought further out, collecting a net credit. The maximum loss is the distance between the strikes minus the credit — known before entry. The building block of all three families.
- Logic variant
- One named strategy rule in the Cashflow Engine Strategy Browser — for example meic_both, put_520, or ratio_1p2c. A variant is the rule; filling in width, premium, stop-loss and entry time turns it into a strategy you could place. There are 14 variants.
- EMA crossover gate
- The entry filter that gives METF its direction: a comparison of a fast and a slow exponential moving average of the index at the entry minute, admitting put spreads when the fast EMA is above the slow one and call spreads when it is below.
- 0DTE
- Zero days to expiration — options traded on their expiration date. SPX offers an expiration every trading day via SPXW, which is what makes daily multiple-entry strategies possible.
Mandatory pit stop: Options trading involves significant risks and is not suitable for every investor. Past results are no guarantee of future performance.