Jesse Pennington pleaded guilty to distributing a Schedule I controlled substance in violation of 21 U.S.C. § 841(a)(1). The district court sentenced her to one year and one day in prison, within the Sentencing Guidelines range of ten to sixteen months in prison. Pennington does not argue that her sentence was substantively unreasonable, but she argues that the district court made procedural errors in sentencing her. She first argues that the district court should not have compared her to one of her co-defendants when determining her sentence because the two were not similarly situated. Next, she argues that the court violated her due process rights by twice relying on inaccurate information at sentencing.
We affirm. The district court's comparison of Pennington to her co-defendant was not a procedural error. The comparison was reasonable and did not exclude consideration of other factors that 18 U.S.C. § 3553(a) requires courts to consider. We also find that the court did not violate Pennington's due process rights by relying on inaccurate information. Although the judge made a factual error in explaining the sentence orally, he corrected the error in the written explanation, indicating that the error did not affect the ultimate sentence.
I. Factual and Procedural Background
In the autumn of 2015, law enforcement in Madison, Wisconsin, began investigating a ring distributing methylenedioxymethamphetamine, more commonly known as MDMA or Ecstasy, and other controlled substances. An undercover officer bought Ecstasy from Pennington twice in late 2015. The officer also met with Pennington on two other occasions around that time intending to purchase Ecstasy, but the officer never completed those sales. In *237September 2016, the officer again twice bought Ecstasy from Pennington. And in October 2016, the officer tried to purchase crack cocaine from Pennington, but she lacked direct access to that drug.
A grand jury indicted Pennington and three others, including JonPaul Dotson, on a total of eleven counts of distributing Ecstasy and crack cocaine. The indictment charged Pennington in two of the counts. She pleaded guilty to one.
At the sentencing hearing, the government requested a prison sentence within the undisputed guideline range of ten to sixteen months. Pennington's involvement in the drug ring was at "the bottom rung of the ladder," the government acknowledged, and the court also already had sentenced Pennington's three co-defendants: two of them to four years in prison, and Dotson to about seven months of time served in pretrial detention. The judge noted that Dotson was "probably ... the smallest" rung of the ladder, a characterization that the government agreed with because Dotson "did one distribution [of crack cocaine] on one occasion." Pennington argued for probation rather than prison. Arguing that Pennington "needs help, not punishment," her lawyer emphasized Pennington's traumatic life experiences, her need to care for her children, and her cooperation with law enforcement.
The judge sentenced Pennington to one year and one day. (The "and one day" meant that she would be eligible to earn a 15% good-time credit. See 18 U.S.C. § 3624(b).) The judge stated that "the biggest driver" of the sentence was the seriousness of the crime and the need to avoid "unwarranted disparities between similarly-situated defendants." Pennington was more culpable than Dotson, the judge found, because Dotson "was involved in essentially one transaction." The judge explained:
You were involved in a pattern of drug dealing that began as early as October 2014 and went through October ['16] There might be a gap in there where there aren't continuous transactions, but there was a sustained period of time of almost two years ... that begins in the fall of October '14 and continues to October '16. Even if it wasn't thoroughly continuous, it was a long period of drug dealing.
The record shows, however, that Pennington's involvement with the drug operation actually began in 2015, not 2014.
The judge deemed it unfair to give Pennington a sentence of probation when "even Mr. Dotson ... ended up serving a term of incarceration" (i.e., pretrial detention). He also mentioned Pennington's "very difficult upbringing," but he added that Pennington is not "necessarily a very good historian of her own past." The judge observed that Pennington deserved a sentence at the low end of the guideline range because she had accepted responsibility for her actions and co-operated with the authorities. In his written statement of reasons, the judge reiterated much of his explanation, with one important change: he corrected his oral error and wrote accurately that Pennington's "drug dealing activities began as early as fall 2015 and continued in the fall of 2016."
II. Analysis
On appeal, Pennington argues that the court committed procedural errors by failing to consider properly all of the 18 U.S.C. § 3553(a) factors and relying on inaccurate information to determine her sentence. She contends that the district court erroneously focused almost exclusively on her culpability relative to JonPaul Dotson, who she argues was not similarly situated. She further argues that the judge procedurally erred by relying on *238inaccurate information because she is not a "poor historian" of her traumatic past and because she did not sell drugs for the "sustained period of time" of two years.
A. Standard of Review
The government argues that Pennington forfeited these arguments by not raising them in the district court. Pennington points out correctly that Federal Rule of Criminal Procedure 51(a) provides that a party need not state an "exception" to a ruling the court has already made. See, e.g., United States v. Bartlett , 567 F.3d 901, 910 (7th Cir. 2009) ("the rules do not require a litigant to complain about a judicial choice after it has been made"). Pennington's arguments on appeal challenge the district court's explanation of its sentencing decision. If she had made them in the district court, they would have been the kind of post-decision exceptions that Rule 51(a) provides a party need not raise to preserve her appellate rights. See United States v. Cunningham , 429 F.3d 673, 679-80 (7th Cir. 2005). Either party, however, could have avoided this appeal by speaking up. See United States v. Donelli , 747 F.3d 936, 941 (7th Cir. 2014) ; Cunningham , 429 F.3d at 679-80.
Both of Pennington's claims-that the district court failed to consider the § 3553(a) factors properly and that it relied on inaccurate information-assert procedural errors. See Gall v. United States , 552 U.S. 38, 51, 128 S.Ct. 586, 169 L.Ed.2d 445 (2007). In the absence of forfeiture, we review the sentencing court's procedure de novo . United States v. Pulley , 601 F.3d 660, 664 (7th Cir. 2010), citing United States v. Smith , 562 F.3d 866, 872 (7th Cir. 2009). We review underlying factual findings for clear error. Id. , citing United States v. Heckel , 570 F.3d 791, 793 (7th Cir. 2009).
B. Section 3553(a) Factors
Pennington argues that the sentencing court erred by failing to give meaningful consideration to the § 3553(a) factors that must be considered in federal sentencing.1
*239She first argues that § 3553(a)(6), which instructs courts to avoid sentencing disparities among defendants with similar records and criminal conduct, does not justify comparing co-defendants in the same case. She also argues that the district court focused on comparing her to Dotson to the exclusion of all the other § 3553(a) factors. We disagree.
As an initial matter, Pennington is incorrect in saying that the "unwarranted disparities" factor in § 3553(a)(6) applies only to defendants across districts and not to co-defendants in the same case. See United States v. Solomon , 892 F.3d 273, 278 (7th Cir. 2018), citing Gall , 552 U.S. at 55-56, 128 S.Ct. 586. And although a sentencing judge must consider each factor, she need not give them all the same weight. The judge is afforded great discretion in weighing the different factors. See Gall , 552 U.S. at 52-56, 128 S.Ct. 586. Here, the judge mentioned Pennington's history and characteristics but ultimately found that the seriousness of the crime and the need to avoid sentencing disparities justified a sentence higher than the probation Pennington requested. The judge also credited Pennington's cooperation with law enforcement, relying on this fact in issuing a sentence toward the bottom of the Guidelines range. Because the judge adequately considered the § 3553(a) factors, there was no procedural error on this score.
Pennington also argues that the court violated her right to an "individualized" sentence by linking her sentence to Dotson's. See Gall , 552 U.S. at 50, 128 S.Ct. 586. But Dotson's seven-month sentence was not random or happenstance. The judge found that seven months was "reasonable and no greater than necessary." See § 3553(a). Because Pennington was more culpable than Dotson-and because the other § 3553(a) factors did not require a below-guideline sentence-the court arrived at a sentence for her that it similarly found reasonable and no greater than necessary.
C. Accuracy of Information at Sentencing
A defendant has a due process right to be sentenced based on accurate information. United States v. Tucker , 404 U.S. 443, 447, 92 S.Ct. 589, 30 L.Ed.2d 592 (1972) ; U.S. ex rel. Welch v. Lane , 738 F.2d 863, 864-65 (7th Cir. 1984). To succeed on this attack on her sentence, Pennington must show that inaccurate information was before the court and that the court relied upon it. United States v. Oliver , 873 F.3d 601, 608-09 (7th Cir. 2017), citing Lechner v. Frank , 341 F.3d 635, 639 (7th Cir. 2003). Pennington argues that the district court violated this principle twice-first when the judge said that she was not "necessarily a very good historian of her own past," and again when he said *240that she had sold drugs for two years instead of one. Again, we disagree.
It is difficult to construe the judge's passing comment that Pennington is a poor historian of her past as a factual finding. Even if it were, "we defer to a district court's determination of witness credibility, which can virtually never be clear error." Pulley , 601 F.3d at 664, citing United States v. Acosta , 534 F.3d 574, 584 (7th Cir. 2008) ; see generally Anderson v. City of Bessemer City , 470 U.S. 564, 575, 105 S.Ct. 1504, 84 L.Ed.2d 518 (1985). We need not repeat Pennington's various inconsistencies and memory lapses that supported the judge's comment. The judge's comment was not clearly erroneous.
The closest question in this appeal stems from a factual mistake in the court's sentencing explanation. The judge said that Pennington had been involved in selling drugs for two years beginning in 2014 rather than only in the autumns of 2015 and 2016. Such factual errors in a judge's explanation of a sentence can easily require a remand for re-sentencing based on accurate information if there are indications that the inaccurate information mattered in the sentencing decision. E.g., United States v. Miller , 900 F.3d 509, 513-14 (2018) (finding plain error and remanding where district judge stated wrong number of defendant's prior felony convictions, both orally and in written explanation); United States v. Corona-Gonzalez , 628 F.3d 336, 342-43 (7th Cir. 2010) (finding plain error and remanding where presentence report said erroneously that defendant had previously been deported and had returned to United States to distribute methamphetamine, and court emphasized those points in explaining sentence); Welch , 738 F.2d at 865-66 (affirming writ of habeas corpus where sentencing judge incorrectly thought defendant had prior conviction for armed robbery instead of robbery).
In this case, however, we are satisfied that this error was corrected in the court's written explanation of reasons, indicating that the difference between the accurate and inaccurate information did not actually affect the sentence. When oral and written pronouncements of a sentence conflict, the oral controls so long as it was unambiguous. United States v. Daddino , 5 F.3d 262, 266 (7th Cir. 1993), quoting United States v. Makres , 851 F.2d 1016, 1019 (7th Cir. 1988).2
While that is the rule for a pronouncement of a sentence itself, we have not applied the same strict rule to a judge's explanation of a sentence. In fact, we have held the opposite. United States v. Pankow , 884 F.3d 785, 791 (7th Cir. 2018) ("In addition to the court's remarks at sentencing, we also look to the written statement of reasons to evaluate the sufficiency of the sentencing rationale."), citing United States v. Blackman , 830 F.3d 721, 728 (7th Cir. 2016) (collecting cases). The judge's written explanation corrected his oral misstatement of the facts without changing the sentence itself. That correction distinguishes this case from United States v. Miller , where we remanded a sentence where the judge had misstated the defendant's criminal history a total of four times, including both oral and written explanations. 900 F.3d at 513-15. We conclude from the written correction that, in the end, whether Pennington sold Ecstasy for one year or two years did not affect her sentence. More material was that she engaged in more drug dealing than Dotson-a *241fact that is true regardless of the court's initial oral misstatement.
Pennington's sentence is AFFIRMED.