By the Numbers

Updated: June 2, 2015

How many centrifuges does Iran have? How much uranium? Does Iran have enough material to produce a nuclear weapon, given a decision to do to?

The below graphs use data as documented in IAEA Board Of Governors Safeguard Reports to plot historical observations of Iran’s uranium enrichment program and show the current status of Iran’s program. Data is organized by date reported by the IAEA. Uranium holdings are expressed as kilograms of U235 in form UF6. If the most recent report does not include complete data on an element of Iran’s program, the previous best-known value is reported.

Source data: Iran Fact File’s compilation of data from Iran’s IAEA safeguards reports is available in this google spreadsheet.

Figure 1: How Close is Iran to the “Red Line” of Sufficient Enriched Uranium for a Bomb?

It takes approximately 250 kg of uranium enriched to near-20% to have sufficient fissile material for a bomb. This graph, comparing Iran’s current uranium stocks to that threshold, shows how close Iran is to notional “red lines.”

The size of Iran’s near-20%  enriched uranium holdings is estimated using the following calculation:

(kg cumulative production of 19.75% LEU) – (kg cumulative 19.75% LEU downblended to near-5%) – (kg cumulative 19.75% converted into U3O8 for reactor fuel production) = Estimated near-20% LEU holdings.

Figure 2: Current Number of Installed Centrifuges by Location

Iran enriches uranium at three facilities: the Natanz, Fordow and Pilot fuel enrichment plants. This graph shows the number of installed centrifuges in each facility, according to the IAEA.

Figure 3: Latest Accounting of Iran’s Uranium Stockpile by Form

Figure 4: Centrifuge Trends at Iran’s Enrichment Facilities

This graph shows the number of centrifuges installed in Iran’s enrichment facilities over time, including at facilities for testing advanced centrifuges.

Figure 5: Iran’s Estimated Uranium Holdings by Level of Enrichment

Graph 1: The size of Iran’s near-3.5%  enriched uranium holdings is estimated using the following calculation:

(kg cumulative production of 3.5% LEU) – (kg cumulative 3.5% LEU further processed) = Estimated near-3.5% LEU holdings.

Graph 2: The size of Iran’s near-20%  enriched uranium holdings is estimated using the following calculation:

(kg cumulative production of 19.75% LEU) – (kg cumulative 19.75% LEU downblended to near-5%) – (kg cumulative 19.75% converted into U3O8 for reactor fuel production) = Estimated near-20% LEU holdings